1
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Malik M, Senatore R, Castiglione D, Roller-Prado A, Pace V. Highly chemoselective homologative assembly of the α-substituted methylsulfinamide motif from N-sulfinylamines. Chem Commun (Camb) 2023; 59:11065-11068. [PMID: 37644820 DOI: 10.1039/d3cc03326k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
α-Substituted methylsulfinamide are prepared through the homologation of electrophilic N-sulfinylamines with Li-CHXY reagents. The transformation takes place under full chemocontrol and exhibits good flexibility for preparing both N-aryl and N-alkyl analogues. Various sensitive functionalities can be accommodated on the starting materials, thus documenting a wide reaction scope.
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Affiliation(s)
- Monika Malik
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Josef-Holaubek-Platz 2, 1090, Vienna, Austria.
| | - Raffaele Senatore
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Josef-Holaubek-Platz 2, 1090, Vienna, Austria.
| | - Davide Castiglione
- Department of Chemistry, Via Giuria 7, University of Turin, Turin 10125, Italy
| | - Alexander Roller-Prado
- Department of Inorganic Chemistry - Functional Materials, University of Vienna, Waehringerstrasse 42, 1090, Vienna, Austria
| | - Vittorio Pace
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Josef-Holaubek-Platz 2, 1090, Vienna, Austria.
- Department of Chemistry, Via Giuria 7, University of Turin, Turin 10125, Italy
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2
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Bao CC, Du HZ, Luo YL, Guan BT. Direct alkylation of N,N-dialkyl benzamides with methyl sulfides under transition metal-free conditions. Commun Chem 2021; 4:138. [PMID: 36697564 PMCID: PMC9814863 DOI: 10.1038/s42004-021-00575-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 08/19/2021] [Indexed: 01/28/2023] Open
Abstract
Amides are a fundamental and widespread functional group, and are usually considered as poor electrophiles owing to resonance stabilization of the amide bond. Various approaches have been developed to address challenges in amide transformations. Nonetheless, most methods use activated amides, organometallic reagents or transition metal catalysts. Here, we report the direct alkylation of N,N-dialkyl benzamides with methyl sulfides promoted by the readily available base LDA (lithium diisopropylamide). This approach successfully achieves an efficient and selective synthesis of α-sulfenylated ketones without using transition-metal catalysts or organometallic reagents. Preliminary mechanism studies reveal that the deprotonative aroylation of methyl sulfides is promoted by the directed ortho-lithiation of the tertiary benzamide with LDA.
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Affiliation(s)
- Can-Can Bao
- grid.216938.70000 0000 9878 7032College of Chemistry, Nankai University, Tianjin, China
| | - Hui-Zhen Du
- grid.216938.70000 0000 9878 7032College of Chemistry, Nankai University, Tianjin, China
| | - Yan-Long Luo
- grid.216938.70000 0000 9878 7032College of Chemistry, Nankai University, Tianjin, China
| | - Bing-Tao Guan
- grid.8547.e0000 0001 0125 2443Department of Chemistry, Fudan University, Shanghai, China
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3
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Rahman MM, Szostak M. Synthesis of Sulfoxonium Ylides from Amides by Selective N-C(O) Activation. Org Lett 2021; 23:4818-4822. [PMID: 34096314 DOI: 10.1021/acs.orglett.1c01535] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The direct synthesis of sulfoxonium ylides from amides by selective N-C(O) cleavage is presented. The reaction proceeds through the nucleophilic addition of dimethylsulfoxonium methylide to the amide bond in acyclic twisted amides under exceedingly mild room temperature conditions. A variety of amides can be employed, and the protocol can be applied to the late-stage derivatization of pharmaceuticals. Mechanistic studies outline the relative order of reactivity of amides.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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4
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Li G, Szostak M. Synthesis of biaryl ketones by arylation of Weinreb amides with functionalized Grignard reagents under thermodynamic control vs. kinetic control of N,N-Boc 2-amides. Org Biomol Chem 2021; 18:3827-3831. [PMID: 32396595 DOI: 10.1039/d0ob00813c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A highly efficient method for chemoselective synthesis of biaryl ketones by arylation of Weinreb amides (N-methoxy-N-methylamides) with functionalized Grignard reagents is reported. This protocol offers rapid entry to functionalized biaryl ketones after Mg/halide exchange with i-PrMgCl·LiCl under operationally-simple and practical reaction conditions. The scope of the method is highlighted in >40 examples, including bioactive compounds and pharmaceutical derivatives. Collectively, this transition-metal-free approach offers a major advantage over the recently established cross-coupling of amides by oxidative addition of N-C(O) bonds. Considering the utility of amide acylation reactions in modern synthesis, we expect that this method will be of broad interest.
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Affiliation(s)
- Guangchen Li
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
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5
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Touqeer S, Ielo L, Miele M, Urban E, Holzer W, Pace V. Direct and straightforward transfer of C1 functionalized synthons to phosphorous electrophiles for accessing gem-P-containing methanes. Org Biomol Chem 2021; 19:2425-2429. [PMID: 33666635 DOI: 10.1039/d1ob00273b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The direct transfer of different α-substituted methyllithium reagents to chlorinated phosphorous electrophiles of diverse oxidation state (phosphates, phosphine oxides and phosphines) is proposed as an effective strategy to synthesize geminal P-containing methanes. The methodology relies on the efficient nucleophilic substitution conducted on the P-chlorine linkage. Uniformly high yields are observed regardless the specific nature of the carbanion employed: once established the conditions for generating the competent nucleophile (LiCH2Hal, LiCHHal2, LiCH2CN, LiCH2SeR etc.) the homologated compounds are obtained via a single operation. Some P-containing formal carbanions have been evaluated in transferring processes, including the carbonyl-difluoromethylation of the opioid agent Hydrocodone.
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Affiliation(s)
- Saad Touqeer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, Vienna, Austria
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6
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Ielo L, Miele M, Pillari V, Senatore R, Mirabile S, Gitto R, Holzer W, Alcántara AR, Pace V. Taking advantage of lithium monohalocarbenoid intrinsic α-elimination in 2-MeTHF: controlled epoxide ring-opening en route to halohydrins. Org Biomol Chem 2021; 19:2038-2043. [PMID: 33599644 DOI: 10.1039/d0ob02407d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The intrinsic degradative α-elimination of Li carbenoids somehow complicates their use in synthesis as C1-synthons. Nevertheless, we herein report how boosting such an α-elimination is a straightforward strategy for accomplishing controlled ring-opening of epoxides to furnish the corresponding β-halohydrins. Crucial for the development of the method is the use of the eco-friendly solvent 2-MeTHF, which forces the degradation of the incipient monohalolithium, due to the very limited stabilizing effect of this solvent on the chemical integrity of the carbenoid. With this approach, high yields of the targeted compounds are consistently obtained under very high regiocontrol and, despite the basic nature of the reagents, no racemization of enantiopure materials is observed.
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Affiliation(s)
- Laura Ielo
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria. and University of Turin - Department of Chemistry, Via P. Giuria 7, 10125, Turin, Italy
| | - Margherita Miele
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Veronica Pillari
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Raffaele Senatore
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Salvatore Mirabile
- University of Messina - Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, Viale Palatucci, 13, 98168 Messina, Italy
| | - Rosaria Gitto
- University of Messina - Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, Viale Palatucci, 13, 98168 Messina, Italy
| | - Wolfgang Holzer
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria.
| | - Andrés R Alcántara
- Complutense University of Madrid - Department of Chemistry in Pharmaceutical Sciences, Plaza de Ramón y Cajal, s/n, Madrid, Spain.
| | - Vittorio Pace
- University of Vienna - Department of Pharmaceutical Chemistry, Althanstrasse, 14, 1090, Vienna, Austria. and University of Turin - Department of Chemistry, Via P. Giuria 7, 10125, Turin, Italy
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7
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Senatore R, Malik M, Touqeer S, Listro R, Collina S, Holzer W, Pace V. Straightforward and direct access to β-seleno- amines and sulfonylamides via the controlled addition of phenylselenomethyllithium (LiCH2SePh) to imines. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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8
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Miele M, Citarella A, Langer T, Urban E, Zehl M, Holzer W, Ielo L, Pace V. Chemoselective Homologation-Deoxygenation Strategy Enabling the Direct Conversion of Carbonyls into ( n+1)-Halomethyl-Alkanes. Org Lett 2020; 22:7629-7634. [PMID: 32910659 PMCID: PMC8011987 DOI: 10.1021/acs.orglett.0c02831] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
![]()
The sequential installation
of a carbenoid and a hydride into a
carbonyl, furnishing halomethyl alkyl derivatives, is reported. Despite
the employment of carbenoids as nucleophiles in reactions with carbon-centered
electrophiles, sp3-type alkyl halides remain elusive materials
for selective one-carbon homologations. Our tactic levers on using
carbonyls as starting materials and enables uniformly high yields
and chemocontrol. The tactic is flexible and is not limited to carbenoids.
Also, diverse carbanion-like species can act as nucleophiles, thus
making it of general applicability.
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Affiliation(s)
- Margherita Miele
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Andrea Citarella
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria.,Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno D'Alcontres, 31, 98166 Messina, Italy
| | - Thierry Langer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Ernst Urban
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Martin Zehl
- Faculty of Chemistry - Department of Analytical Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Laura Ielo
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria.,Department of Chemistry, University of Turin, Via P. Giuria 7, 10125 Turin, Italy
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9
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Buchspies J, Rahman MM, Szostak R, Szostak M. N-Acylcarbazoles and N-Acylindoles: Electronically Activated Amides for N–C(O) Cross-Coupling by Nlp to Ar Conjugation Switch. Org Lett 2020; 22:4703-4709. [DOI: 10.1021/acs.orglett.0c01488] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jonathan Buchspies
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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10
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Ielo L, Pillari V, Gajic N, Holzer W, Pace V. Straightforward chemoselective access to unsymmetrical dithioacetals through a thiosulfonate homologation-nucleophilic substitution sequence. Chem Commun (Camb) 2020; 56:12395-12398. [PMID: 32935694 DOI: 10.1039/d0cc04896h] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A two-step electrophilic sulfur homologation strategy for building up unsymmetrical dithioacetals.
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Affiliation(s)
- Laura Ielo
- Department of Pharmaceutical Chemistry
- University of Vienna
- Vienna
- Austria
| | - Veronica Pillari
- Department of Pharmaceutical Chemistry
- University of Vienna
- Vienna
- Austria
| | - Natalie Gajic
- X-Ray Structure Analysis Center
- University of Vienna
- Vienna
- Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry
- University of Vienna
- Vienna
- Austria
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry
- University of Vienna
- Vienna
- Austria
- Department of Chemistry
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11
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Kohlbacher SM, Ionasz VS, Ielo L, Pace V. The synthetic versatility of the Tiffeneau–Demjanov chemistry in homologation tactics. MONATSHEFTE FUR CHEMIE 2019. [DOI: 10.1007/s00706-019-02514-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Abstract
The Tiffeneau–Demjanov rearrangement can be regarded as an interesting alternative to the more common semi-pinacol transposition. It is usually employed for ring extension but, under specific conditions, it can also be used for ring contraction. Compared to other techniques, such as the Demjanov rearrangement or homologations with diazo compounds, the Tiffeneau–Demjanov pathway presents attractive features including high yielding and selective processes. Ring enlargements follow very strict and simple rules, such as the movement of the less substituted carbon and retention of the configuration. The rearrangement process is mainly affected by steric factors, due to presence of neighbouring groups, rather than electronic ones. The ring contraction may be achieved positioning the amine within the ring, thus achieving a high level of control. Unfortunately, applications of the reaction in modern homologation chemistry are rare; therefore, the aim of the review is re-proposing to the synthetic community the versatility of this venerable reaction and thus, spurring its employment for tackling challenging homologations processes.
Graphic abstract
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12
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Miele M, D'Orsi R, Sridharan V, Holzer W, Pace V. Highly chemoselective difluoromethylative homologation of iso(thio)cyanates: expeditious access to unprecedented α,α-difluoro(thio)amides. Chem Commun (Camb) 2019; 55:12960-12963. [PMID: 31602439 DOI: 10.1039/c9cc06929a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The new motif - α,α-difluoromethyl thioamide - has been assembled starting from isothiocyanate (as thioamide precursor) and a formal difluoromethyl-carbanion generated from commercially available TMSCHF2. Upon proper activation of this reagent with potassium tert-amylate, the high-yielding transfer of the difluorinated nucleophile takes place under high chemocontrol. Various sensitive functionalities (e.g. ester, nitrile, nitro, azido groups) can be accommodated across the isothiocyanate core, thus allowing a wide scope. The methodology is highly flexible and adaptable to prepare analogous α,α-difluoromethyl oxoamides by conveniently using isocyanates as the electrophilic building-blocks.
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Affiliation(s)
- Margherita Miele
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
| | - Rosarita D'Orsi
- Department of Sciences, University of Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Vellaisamy Sridharan
- Department of Chemistry and Chemical Sciences, Central University of Jammu, Rahya-Suchani (Bagla), 181143, India
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
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13
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Miele M, Citarella A, Micale N, Holzer W, Pace V. Direct and Chemoselective Synthesis of Tertiary Difluoroketones via Weinreb Amide Homologation with a CHF 2-Carbene Equivalent. Org Lett 2019; 21:8261-8265. [PMID: 31599599 DOI: 10.1021/acs.orglett.9b03024] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The homologation of Weinreb amides into difluoromethylketones with a formal nucleophilic CHF2 transfer agent is reported. Activating TMSCHF2 with potassium tert-amylate enables a convenient access to the difluorinated homologation reagent, which adds to the acylating partners. The high chemoselectivity showcased in the presence of variously multifunctionalized Weinreb amides, jointly with uniformly high yields, enables the strategy of general applicability without requiring any stabilization element for the putative carbanion.
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Affiliation(s)
- Margherita Miele
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse, 14 , 1090 Vienna , Austria
| | - Andrea Citarella
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse, 14 , 1090 Vienna , Austria.,University of Messina , Department of Chemical, Biological, Pharmaceutical and Environmental Sciences , Viale F. Stagno D'Alcontres, 31 , 98166 Messina , Italy
| | - Nicola Micale
- University of Messina , Department of Chemical, Biological, Pharmaceutical and Environmental Sciences , Viale F. Stagno D'Alcontres, 31 , 98166 Messina , Italy
| | - Wolfgang Holzer
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse, 14 , 1090 Vienna , Austria
| | - Vittorio Pace
- University of Vienna , Department of Pharmaceutical Chemistry , Althanstrasse, 14 , 1090 Vienna , Austria
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14
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Monticelli S, Holzer W, Langer T, Roller A, Olofsson B, Pace V. Sustainable Asymmetric Organolithium Chemistry: Enantio- and Chemoselective Acylations through Recycling of Solvent, Sparteine, and Weinreb "Amine". CHEMSUSCHEM 2019; 12:1147-1154. [PMID: 30614208 PMCID: PMC6704367 DOI: 10.1002/cssc.201802815] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 12/20/2018] [Indexed: 05/10/2023]
Abstract
The well-established Hoppe-Beak chemistry, which involves enantioselective generation of organolithium compounds in the presence of (-)-sparteine, was revisited and applied to unprecedented acylations with Weinreb amides to access highly enantioenriched α-oxyketones and cyclic α-aminoketones. Recycling of the sustainable solvent cyclopentyl methyl ether, sparteine, and the released Weinreb "amine" [HNMe(OMe)] was possible through a simple work-up procedure that enabled full recovery of these precious materials. The methodology features a robust scope and flexibility, thus allowing the enantioselective preparation of scaffolds amenable of further derivatization.
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Affiliation(s)
- Serena Monticelli
- Department of Pharmaceutical ChemistryUniversity of ViennaAlthanstrasse,14Vienna1090Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical ChemistryUniversity of ViennaAlthanstrasse,14Vienna1090Austria
| | - Thierry Langer
- Department of Pharmaceutical ChemistryUniversity of ViennaAlthanstrasse,14Vienna1090Austria
| | - Alexander Roller
- X-Ray Structure Analysis CenterUniversity of ViennaWaehringerstrasse 42Vienna1090Austria
| | - Berit Olofsson
- Department of Organic Chemistry, Arrhenius LaboratoryStockholm UniversitySe-106 91StockholmSweden
| | - Vittorio Pace
- Department of Pharmaceutical ChemistryUniversity of ViennaAlthanstrasse,14Vienna1090Austria
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15
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Castoldi L, Monticelli S, Senatore R, Ielo L, Pace V. Homologation chemistry with nucleophilic α-substituted organometallic reagents: chemocontrol, new concepts and (solved) challenges. Chem Commun (Camb) 2018; 54:6692-6704. [PMID: 29850663 DOI: 10.1039/c8cc02499e] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The transfer of a reactive nucleophilic CH2X unit into a preformed bond enables the introduction of a fragment featuring the exact and desired degree of functionalization through a single synthetic operation. The instability of metallated α-organometallic species often poses serious questions regarding the practicability of using this conceptually intuitive and simple approach for forming C-C or C-heteroatom bonds. A deep understanding of processes regulating the formation of these nucleophiles is a precious source of inspiration not only for successfully applying theoretically feasible transformations (i.e. determining how to employ a given reagent), but also for designing new reactions which ultimately lead to the introduction of molecular complexity via short experimental sequences.
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Affiliation(s)
- Laura Castoldi
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstrasse, 14, A-1090, Vienna, Austria.
| | - Serena Monticelli
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstrasse, 14, A-1090, Vienna, Austria.
| | - Raffaele Senatore
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstrasse, 14, A-1090, Vienna, Austria.
| | - Laura Ielo
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstrasse, 14, A-1090, Vienna, Austria.
| | - Vittorio Pace
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstrasse, 14, A-1090, Vienna, Austria.
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16
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Monticelli S, Rui M, Castoldi L, Missere G, Pace V. A practical guide for using lithium halocarbenoids in homologation reactions. MONATSHEFTE FUR CHEMIE 2018; 149:1285-1291. [PMID: 29983454 PMCID: PMC6006224 DOI: 10.1007/s00706-018-2232-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 05/13/2018] [Indexed: 12/24/2022]
Abstract
ABSTRACT Lithium halocarbenoids are versatile reagents for accomplishing homologation processes. The fast α-elimination they suffer has been considered an important limitation for their extensive use. Herein, we present a series of practical considerations for an effective employment in the homologation of selected carbon electrophiles. GRAPHICAL ABSTRACT
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Affiliation(s)
- Serena Monticelli
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Marta Rui
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Laura Castoldi
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Giada Missere
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
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