1
|
Cross MJ, Brodie CN, Crivoi DG, Goodall JC, Ryan DE, Martínez‐Martínez AJ, Johnson A, Weller AS. Dehydropolymerization of Amine-Boranes using Bis(imino)pyridine Rhodium Pre-Catalysis: σ-Amine-Borane Complexes, Nanoparticles, and Low Residual-Metal BN-Polymers that can be Chemically Repurposed. Chemistry 2023; 29:e202302110. [PMID: 37530441 PMCID: PMC10947130 DOI: 10.1002/chem.202302110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/03/2023]
Abstract
The sigma amine-borane complexes [Rh(L1)(η2 :η2 -H3 B⋅NRH2 )][OTf] (L1=2,6-bis-[1-(2,6-diisopropylphenylimino)ethyl]pyridine, R=Me, Et, n Pr) are described, alongside [Rh(L1)(NMeH2 )][OTf]. Using R=Me as a pre-catalyst (1 mol %) the dehydropolymerization of H3 B ⋅ NMeH2 gives [H2 BNMeH]n selectively. Added NMeH2 , or the direct use of [Rh(L1)(NMeH2 )][OTf], is required for initiation of catalysis, which is suggested to operate through the formation of a neutral hydride complex, Rh(L1)H. The formation of small (1-5 nm) nanoparticles is observed at the end of catalysis, but studies are ambiguous as to whether the catalysis is solely nanoparticle promoted or if there is a molecular homogeneous component. [Rh(L1)(NMeH2 )][OTf] is shown to operate at 0.025 mol % loadings on a 2 g scale of H3 B ⋅ NMeH2 to give polyaminoborane [H2 BNMeH]n [Mn =30,900 g/mol, Ð=1.8] that can be purified to a low residual [Rh] (6 μg/g). Addition of Na[N(SiMe3 )2 ] to [H2 BNMeH]n results in selective depolymerization to form the eee-isomer of N,N,N-trimethylcyclotriborazane [H2 BNMeH]3 : the chemical repurposing of a main-group polymer.
Collapse
Affiliation(s)
| | | | - Dana G. Crivoi
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
| | | | - David E. Ryan
- Department of ChemistryUniversity of YorkYorkYO10 5DDUK
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
| | - Antonio J. Martínez‐Martínez
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
- Supramolecular Organometallic and Main Group Chemistry Laboratory CIQSO-Center for Research in Sustainable Chemistry and Department of ChemistryUniversity of HuelvaCampus El Carmen21007HuelvaSpain
| | - Alice Johnson
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
- Department of Biosciences and ChemistrySheffield Hallam UniversityHoward StSheffieldS1 1WBUK
| | | |
Collapse
|
2
|
Peng C, Liu W, Wang Y. Mechanistic insights into H 3B·NMeH 2 dehydrogenation by Co-based complexes: a DFT perspective. NEW J CHEM 2023. [DOI: 10.1039/d2nj06155d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
Mechanistic insights into Co-catalyzed H3B·NMeH2 dehydrogenation and polyaminoborane formation are carefully investigated using density functional theory.
Collapse
Affiliation(s)
- Cheng Peng
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Wei Liu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Yong Wang
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| |
Collapse
|
3
|
Oldroyd NL, Chitnis SS, LaPierre EA, Annibale VT, Walsgrove HTG, Gates DP, Manners I. Ambient Temperature Carbene-Mediated Depolymerization: Stoichiometric and Catalytic Reactions of N-Heterocyclic- and Cyclic(Alkyl)Amino Carbenes with Poly( N-Methylaminoborane) [MeNH–BH 2] n. J Am Chem Soc 2022; 144:23179-23190. [DOI: 10.1021/jacs.2c10931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Nicola L. Oldroyd
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
- Department of Chemistry, University of Victoria, Victoria BC V8W 3V6, Canada
| | - Saurabh S. Chitnis
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Etienne A. LaPierre
- Department of Chemistry, University of Victoria, Victoria BC V8W 3V6, Canada
| | - Vincent T. Annibale
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
- Department of Chemistry, University of Victoria, Victoria BC V8W 3V6, Canada
| | - Henry T. G. Walsgrove
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver V6T 1Z1, British Columbia, Canada
| | - Derek P. Gates
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver V6T 1Z1, British Columbia, Canada
| | - Ian Manners
- Department of Chemistry, University of Victoria, Victoria BC V8W 3V6, Canada
| |
Collapse
|
4
|
Brodie CN, Sotorrios L, Boyd TM, Macgregor SA, Weller AS. Dehydropolymerization of H 3B·NMeH 2 Mediated by Cationic Iridium(III) Precatalysts Bearing κ 3- iPr-PN RP Pincer Ligands ( R = H, Me): An Unexpected Inner-Sphere Mechanism. ACS Catal 2022; 12:13050-13064. [PMID: 36313521 PMCID: PMC9594342 DOI: 10.1021/acscatal.2c03778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/27/2022] [Indexed: 11/30/2022]
Abstract
![]()
The dehydropolymerization of H3B·NMeH2 to form N-methylpolyaminoborane using neutral
and
cationic catalysts based on the {Ir(iPr-PNHP)} fragment [iPr-PNHP = κ3-(CH2CH2PiPr2)2NH] is reported. Neutral
Ir(iPr-PNHP)H3 or
Ir(iPr-PNHP)H2Cl
precatalysts show no, or poor and unselective, activity respectively
at 298 K in 1,2-F2C6H4 solution.
In contrast, addition of [NMeH3][BArF4] (ArF = 3,5-(CF3)2C6H3) to Ir(iPr-PNHP)H3 immediately starts catalysis, suggesting that a cationic
catalytic manifold operates. Consistent with this, independently synthesized
cationic precatalysts are active (tested between 0.5 and 2.0 mol %
loading) producing poly(N-methylaminoborane) with Mn ∼ 40,000 g/mol, Đ ∼1.5, i.e., dihydrogen/dihydride, [Ir(iPr-PNHP)(H)2(H2)][BArF4]; σ-amine-borane [Ir(iPr-PNHP)(H)2(H3B·NMe3)][BArF4]; and [Ir(iPr-PNHP)(H)2(NMeH2)][BArF4]. Density functional theory (DFT) calculations
probe hydride exchange processes in two of these complexes and also
show that the barrier to amine-borane dehydrogenation is lower (22.5
kcal/mol) for the cationic system compared with the neutral system
(24.3 kcal/mol). The calculations show that the dehydrogenation proceeds
via an inner-sphere process without metal–ligand cooperativity,
and this is supported experimentally by N–Me substituted [Ir(iPr-PNMeP)(H)2(H3B·NMe3)][BArF4] being
an active catalyst. Key to the lower barrier calculated for the cationic
system is the outer-sphere coordination of an additional H3B·NMeH2 with the N–H group of the ligand.
Experimentally, kinetic studies indicate a complex reaction manifold
that shows pronounced deceleratory temporal profiles. As supported
by speciation and DFT studies, a key observation is that deprotonation
of [Ir(iPr-NHP)(H)2(H2)][BArF4], formed upon amine-borane
dehydrogenation, by the slow in situ formation of NMeH2 (via B–N bond cleavage), results in the formation of essentially
inactive Ir(iPr-PNHP)H3, with a coproduct of [NMeH3]+/[H2B(NMeH2)2]+. While reprotonation
of Ir(iPr-PNHP)H3 results in a return to the cationic cycle, it is proposed, supported
by doping experiments, that reprotonation is attenuated by entrainment
of the [NMeH3]+/[H2B(NMeH2)2]+/catalyst in insoluble polyaminoborane.
The role of [NMeH3]+/[H2B(NMeH2)]+ as chain control agents is also noted.
Collapse
Affiliation(s)
| | - Lia Sotorrios
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Timothy M. Boyd
- Department of Chemistry, University of York, York YO10 5DD, U.K
- Chemistry Research Laboratories, University of Oxford, Oxford OX1 3TA, U.K
| | - Stuart A. Macgregor
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | | |
Collapse
|
5
|
Brodie CN, Boyd TM, Sotorríos L, Ryan DE, Magee E, Huband S, Town JS, Lloyd-Jones GC, Haddleton DM, Macgregor SA, Weller AS. Controlled Synthesis of Well-Defined Polyaminoboranes on Scale Using a Robust and Efficient Catalyst. J Am Chem Soc 2021; 143:21010-21023. [PMID: 34846131 DOI: 10.1021/jacs.1c10888] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The air tolerant precatalyst, [Rh(L)(NBD)]Cl ([1]Cl) [L = κ3-(iPr2PCH2CH2)2NH, NBD = norbornadiene], mediates the selective synthesis of N-methylpolyaminoborane, (H2BNMeH)n, by dehydropolymerization of H3B·NMeH2. Kinetic, speciation, and DFT studies show an induction period in which the active catalyst, Rh(L)H3 (3), forms, which sits as an outer-sphere adduct 3·H3BNMeH2 as the resting state. At the end of catalysis, dormant Rh(L)H2Cl (2) is formed. Reaction of 2 with H3B·NMeH2 returns 3, alongside the proposed formation of boronium [H2B(NMeH2)2]Cl. Aided by isotopic labeling, Eyring analysis, and DFT calculations, a mechanism is proposed in which the cooperative "PNHP" ligand templates dehydrogenation, releasing H2B═NMeH (ΔG‡calc = 19.6 kcal mol-1). H2B═NMeH is proposed to undergo rapid, low barrier, head-to-tail chain propagation for which 3 is the catalyst/initiator. A high molecular weight polymer is formed that is relatively insensitive to catalyst loading (Mn ∼71 000 g mol-1; Đ, of ∼ 1.6). The molecular weight can be controlled using [H2B(NMe2H)2]Cl as a chain transfer agent, Mn = 37 900-78 100 g mol-1. This polymerization is suggested to arise from an ensemble of processes (catalyst speciation, dehydrogenation, propagation, chain transfer) that are geared around the concentration of H3B·NMeH2. TGA and DSC thermal analysis of polymer produced on scale (10 g, 0.01 mol % [1]Cl) show a processing window that allows for melt extrusion of polyaminoborane strands, as well as hot pressing, drop casting, and electrospray deposition. By variation of conditions in the latter, smooth or porous microstructured films or spherical polyaminoboranes beads (∼100 nm) result.
Collapse
Affiliation(s)
- Claire N Brodie
- Department of Chemistry, University of York, Heslington, York YO31 1ES, U.K
| | - Timothy M Boyd
- Department of Chemistry, University of York, Heslington, York YO31 1ES, U.K.,Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K
| | - Lia Sotorríos
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - David E Ryan
- Department of Chemistry, University of York, Heslington, York YO31 1ES, U.K.,Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K
| | - Eimear Magee
- International Institute for Nanocomposites Manufacturing, WMG, University of Warwick, Coventry CV4 7AL, U.K
| | - Steven Huband
- Department of Physics, University of Warwick, Coventry CV4 7AL, U.K
| | - James S Town
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Guy C Lloyd-Jones
- School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, Scotland, U.K
| | - David M Haddleton
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Stuart A Macgregor
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Andrew S Weller
- Department of Chemistry, University of York, Heslington, York YO31 1ES, U.K
| |
Collapse
|
6
|
Devillard M, De Albuquerque Pinheiro CA, Caytan E, Roiland C, Dinoi C, Del Rosal I, Alcaraz G. Uncatalyzed Formation of Polyaminoboranes from Diisopropylaminoborane and Primary Amines: a Kinetically Controlled Polymerization Reaction. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001458] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Marc Devillard
- Univ Rennes CNRS ISCR (Institut des Sciences Chimiques de Rennes) 35000 Rennes France
| | | | - Elsa Caytan
- Univ Rennes CNRS ISCR (Institut des Sciences Chimiques de Rennes) 35000 Rennes France
| | - Claire Roiland
- Univ Rennes CNRS ISCR (Institut des Sciences Chimiques de Rennes) 35000 Rennes France
| | - Chiara Dinoi
- LPCNO CNRS & INSA Universitć de Toulouse 135 avenue de Rangueil 31077 Toulouse France
| | - Iker Del Rosal
- LPCNO CNRS & INSA Universitć de Toulouse 135 avenue de Rangueil 31077 Toulouse France
| | - Gilles Alcaraz
- Univ Rennes CNRS ISCR (Institut des Sciences Chimiques de Rennes) 35000 Rennes France
| |
Collapse
|
7
|
Resendiz-Lara DA, Annibale VT, Knights AW, Chitnis SS, Manners I. High Molar Mass Poly(alkylphosphinoboranes) via Iron-Catalyzed Dehydropolymerization. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c02082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Vincent T. Annibale
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
- Department of Chemistry, University of Victoria, 3800 Finnerty Road, Victoria, British Columbia V8P 5C2, Canada
| | - Alastair W. Knights
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Saurabh S. Chitnis
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Ian Manners
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
- Department of Chemistry, University of Victoria, 3800 Finnerty Road, Victoria, British Columbia V8P 5C2, Canada
| |
Collapse
|
8
|
Ryan DE, Andrea KA, Race JJ, Boyd TM, Lloyd-Jones GC, Weller AS. Amine–Borane Dehydropolymerization Using Rh-Based Precatalysts: Resting State, Chain Control, and Efficient Polymer Synthesis. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02211] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- David E. Ryan
- Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
- Department of Chemistry, Chemical Research Laboratories, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Kori A. Andrea
- Department of Chemistry, Memorial University of Newfoundland, St. John’s, Newfoundland A1B 3X7, Canada
| | - James J. Race
- Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
- Department of Chemistry, Chemical Research Laboratories, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Timothy M. Boyd
- Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
- Department of Chemistry, Chemical Research Laboratories, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Guy C. Lloyd-Jones
- School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Andrew S. Weller
- Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| |
Collapse
|
9
|
Boyd TM, Andrea KA, Baston K, Johnson A, Ryan DE, Weller AS. A simple cobalt-based catalyst system for the controlled dehydropolymerisation of H3B·NMeH2 on the gram-scale. Chem Commun (Camb) 2020; 56:482-485. [DOI: 10.1039/c9cc08864d] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A simple Co-based catalyst system promotes the efficient and controlled dehydropolymerisation of amine–boranes on scale.
Collapse
Affiliation(s)
- Timothy M. Boyd
- Department of Chemistry
- Chemistry Research Laboratories
- University of Oxford
- Oxford
- UK
| | - Kori A. Andrea
- Department of Chemistry
- Chemistry Research Laboratories
- University of Oxford
- Oxford
- UK
| | - Katherine Baston
- Department of Chemistry
- Chemistry Research Laboratories
- University of Oxford
- Oxford
- UK
| | - Alice Johnson
- Department of Chemistry
- Chemistry Research Laboratories
- University of Oxford
- Oxford
- UK
| | - David E. Ryan
- Department of Chemistry
- Chemistry Research Laboratories
- University of Oxford
- Oxford
- UK
| | - Andrew S. Weller
- Department of Chemistry
- Chemistry Research Laboratories
- University of Oxford
- Oxford
- UK
| |
Collapse
|
10
|
LaPierre EA, Patrick BO, Manners I. Trivalent Titanocene Alkyls and Hydrides as Well-Defined, Highly Active, and Broad Scope Precatalysts for Dehydropolymerization of Amine-Boranes. J Am Chem Soc 2019; 141:20009-20015. [DOI: 10.1021/jacs.9b11112] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Etienne A. LaPierre
- Department of Chemistry, University of Victoria, 3800 Finnerty Road, Victoria, British Columbia V8P 5C2, Canada
| | - Brian O. Patrick
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Ian Manners
- Department of Chemistry, University of Victoria, 3800 Finnerty Road, Victoria, British Columbia V8P 5C2, Canada
| |
Collapse
|
11
|
Spearing-Ewyn EAK, Beattie NA, Colebatch AL, Martinez-Martinez AJ, Docker A, Boyd TM, Baillie G, Reed R, Macgregor SA, Weller AS. The role of neutral Rh(PONOP)H, free NMe 2H, boronium and ammonium salts in the dehydrocoupling of dimethylamine-borane using the cationic pincer [Rh(PONOP)(η 2-H 2)] + catalyst. Dalton Trans 2019; 48:14724-14736. [PMID: 31538996 DOI: 10.1039/c9dt03358k] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The σ-amine-borane pincer complex [Rh(PONOP)(η1-H3B·NMe3)][BArF4] [2, PONOP = κ3-NC5H3-2,6-(OPtBu2)2] is prepared by addition of H3B·NMe3 to the dihydrogen precursor [Rh(PONOP)(η2-H2)][BArF4], 1. In a similar way the related H3B·NMe2H complex [Rh(PONOP)(η1-H3B·NMe2H)][BArF4], 3, can be made in situ, but this undergoes dehydrocoupling to reform 1 and give the aminoborane dimer [H2BNMe2]2. NMR studies on this system reveal an intermediate neutral hydride forms, Rh(PONOP)H, 4, that has been prepared independently. 1 is a competent catalyst (2 mol%, ∼30 min) for the dehydrocoupling of H3B·Me2H. Kinetic, mechanistic and computational studies point to the role of NMe2H in both forming the neutral hydride, via deprotonation of a σ-amine-borane complex and formation of aminoborane, and closing the catalytic cycle by reprotonation of the hydride by the thus-formed dimethyl ammonium [NMe2H2]+. Competitive processes involving the generation of boronium [H2B(NMe2H)2]+ are also discussed, but shown to be higher in energy. Off-cycle adducts between [NMe2H2]+ or [H2B(NMe2H)2]+ and amine-boranes are also discussed that act to modify the kinetics of dehydrocoupling.
Collapse
|
12
|
Resendiz-Lara DA, Whittell GR, Leitao EM, Manners I. Catalytic Synthesis, Characterization, and Properties of Polyaminoborane Homopolymers and Random Copolymers. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01139] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
| | - George R. Whittell
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K
| | - Erin M. Leitao
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K
| | - Ian Manners
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K
- Department of Chemistry, University of Victoria, Victoria, BC V8W 3V6, Canada
| |
Collapse
|
13
|
Han D, Anke F, Trose M, Beweries T. Recent advances in transition metal catalysed dehydropolymerisation of amine boranes and phosphine boranes. Coord Chem Rev 2019. [DOI: 10.1016/j.ccr.2018.09.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
14
|
Colebatch AL, Weller AS. Amine-Borane Dehydropolymerization: Challenges and Opportunities. Chemistry 2019; 25:1379-1390. [PMID: 30338876 PMCID: PMC6391989 DOI: 10.1002/chem.201804592] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Indexed: 11/23/2022]
Abstract
The dehydropolymerization of amine-boranes, exemplified as H2 RB⋅NR'H2 , to produce polyaminoboranes (HRBNR'H)n that are inorganic analogues of polyolefins with alternating main-chain B-N units, is an area with significant potential, stemming from both fundamental (mechanism, catalyst development, main-group hetero-cross-coupling) and technological (new polymeric materials) opportunities. This Concept article outlines recent advances in the field, covering catalyst development and performance, current mechanistic models, and alternative non-catalytic routes for polymer production. The substrate scope, polymer properties and applications of these exciting materials are also outlined. Challenges and opportunities in the field are suggested, as a way of providing focus for future investigations.
Collapse
Affiliation(s)
- Annie L. Colebatch
- Department of ChemistryUniversity of CambridgeLensfield RoadCambridgeCB2 1EWUK
- Department of ChemistryUniversity of OxfordMansfield RoadOxfordOX1 3TAUK
| | - Andrew S. Weller
- Department of ChemistryUniversity of OxfordMansfield RoadOxfordOX1 3TAUK
| |
Collapse
|
15
|
Trose M, Reiß M, Reiß F, Anke F, Spannenberg A, Boye S, Lederer A, Arndt P, Beweries T. Dehydropolymerisation of methylamine borane using a dinuclear 1,3-allenediyl bridged zirconocene complex. Dalton Trans 2018; 47:12858-12862. [PMID: 30156242 DOI: 10.1039/c8dt03311k] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dinuclear zirconocene chloride complex 1 is a highly active precatalyst for the dehydropolymerisation of methylamine borane. Comparison with mononuclear Zr chlorides and related dinuclear complexes suggests that the nature of the bridging motif is essential for the unique reactivity of 1.
Collapse
Affiliation(s)
- M Trose
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - M Reiß
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - F Reiß
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - F Anke
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - A Spannenberg
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - S Boye
- Leibniz-Institut für Polymerforschung Dresden, Hohe Str. 6, 01069 Dresden, Germany
| | - A Lederer
- Leibniz-Institut für Polymerforschung Dresden, Hohe Str. 6, 01069 Dresden, Germany and Technische Universität Dresden, 01062 Dresden, Germany
| | - P Arndt
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - T Beweries
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| |
Collapse
|
16
|
Jurca T, Dellermann T, Stubbs NE, Resendiz-Lara DA, Whittell GR, Manners I. Step-growth titanium-catalysed dehydropolymerisation of amine-boranes. Chem Sci 2018; 9:3360-3366. [PMID: 29780466 PMCID: PMC5933219 DOI: 10.1039/c7sc05395a] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/05/2018] [Indexed: 11/21/2022] Open
Abstract
Precatalysts active for the dehydropolymerisation of primary amine-boranes are generally based on mid or late transition metal. We have found that the activity of the precatalyst system formed from CpR2TiCl2 and 2nBuLi towards the dehydrogenation of the secondary amine-borane Me2NH·BH3, to yield the cyclic diborazane [Me2N-BH2]2, increases dramatically with increasing electron-donating character of the cyclopentadienyl rings (CpR). Application of the most active precatalyst system (CpR = η-C5Me5) to the primary amine-borane MeNH2·BH3 enabled the first synthesis of high molar mass poly(N-methylaminoborane), [MeNH-BH2] n , the BN analogue of polypropylene, by an early transition metal such as catalyst. Significantly, unlike other dehydropolymerization precatalysts for MeNH2·BH3 such as [Ir(POCOP)H2], skeletal nickel, and [Rh(COD)Cl]2, the Ti precatalyst system was also active towards a range of substrates including BzNH2·BH3 (Bz = benzyl) yielding high molar mass polymer. Moreover, in contrast to the late transition metal catalysed dehydropolymerisation of MeNH2·BH3 and also the Ziegler-Natta polymerisation of olefins, studies indicate that the Ti-catalyzed dehydropolymerization reactions proceed by a step-growth rather than a chain-growth mechanism.
Collapse
Affiliation(s)
- Titel Jurca
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , UK .
| | - Theresa Dellermann
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , UK .
| | - Naomi E Stubbs
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , UK .
| | - Diego A Resendiz-Lara
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , UK .
| | - George R Whittell
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , UK .
| | - Ian Manners
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , UK .
| |
Collapse
|
17
|
Adams GM, Colebatch AL, Skornia JT, McKay AI, Johnson HC, Lloyd−Jones GC, Macgregor SA, Beattie NA, Weller AS. Dehydropolymerization of H3B·NMeH2 To Form Polyaminoboranes Using [Rh(Xantphos-alkyl)] Catalysts. J Am Chem Soc 2018; 140:1481-1495. [DOI: 10.1021/jacs.7b11975] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gemma M. Adams
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Annie L. Colebatch
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Joseph T. Skornia
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Alasdair I. McKay
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Heather C. Johnson
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Guy C. Lloyd−Jones
- School
of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Stuart A. Macgregor
- Institute
of Chemical Sciences, Heriot Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Nicholas A. Beattie
- Institute
of Chemical Sciences, Heriot Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Andrew S. Weller
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| |
Collapse
|
18
|
De Albuquerque Pinheiro CA, Roiland C, Jehan P, Alcaraz G. Solventless and Metal-Free Synthesis of High-Molecular-Mass Polyaminoboranes from Diisopropylaminoborane and Primary Amines. Angew Chem Int Ed Engl 2018; 57:1519-1522. [DOI: 10.1002/anie.201710293] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Indexed: 11/10/2022]
Affiliation(s)
| | - Claire Roiland
- Institut des Sciences Chimiques de Rennes (ISCR), UMR-CNRS 6226; Université de Rennes 1; 263 avenue du Général Leclerc 35042 Rennes cedex France
| | - Philippe Jehan
- ScanMAT-CRMPO, UMS-CNRS 2001; Université de Rennes 1; 263 avenue du Général Leclerc 35042 Rennes cedex France
| | - Gilles Alcaraz
- Institut des Sciences Chimiques de Rennes (ISCR), UMR-CNRS 6226; Université de Rennes 1; 263 avenue du Général Leclerc 35042 Rennes cedex France
| |
Collapse
|
19
|
De Albuquerque Pinheiro CA, Roiland C, Jehan P, Alcaraz G. Solventless and Metal-Free Synthesis of High-Molecular-Mass Polyaminoboranes from Diisopropylaminoborane and Primary Amines. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201710293] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Claire Roiland
- Institut des Sciences Chimiques de Rennes (ISCR), UMR-CNRS 6226; Université de Rennes 1; 263 avenue du Général Leclerc 35042 Rennes cedex France
| | - Philippe Jehan
- ScanMAT-CRMPO, UMS-CNRS 2001; Université de Rennes 1; 263 avenue du Général Leclerc 35042 Rennes cedex France
| | - Gilles Alcaraz
- Institut des Sciences Chimiques de Rennes (ISCR), UMR-CNRS 6226; Université de Rennes 1; 263 avenue du Général Leclerc 35042 Rennes cedex France
| |
Collapse
|
20
|
Resendiz-Lara DA, Stubbs NE, Arz MI, Pridmore NE, Sparkes HA, Manners I. Boron–nitrogen main chain analogues of polystyrene: poly(B-aryl)aminoboranes via catalytic dehydrocoupling. Chem Commun (Camb) 2017; 53:11701-11704. [DOI: 10.1039/c7cc07331c] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High molecular weight B-arylated polyaminoboranes are obtained via catalytic dehydropolymerisation of B-aryl amine–boranes and represent the first inorganic polystyrene analogues with a B–N main chain.
Collapse
Affiliation(s)
| | | | - Marius I. Arz
- School of Chemistry
- University of Bristol
- Bristol BS8 1TS
- UK
| | | | | | - Ian Manners
- School of Chemistry
- University of Bristol
- Bristol BS8 1TS
- UK
| |
Collapse
|