1
|
Xu J. Synthetic strategies for the preparation of γ-phostams: 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides. Beilstein J Org Chem 2022; 18:889-915. [PMID: 35957753 PMCID: PMC9344546 DOI: 10.3762/bjoc.18.90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/11/2022] [Indexed: 11/23/2022] Open
Abstract
γ-Phostams include γ-phosphonolactams and γ-phosphinolactams and their fused derivatives, phosphorus analogues of γ-lactams. They are 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides and important biological five-membered azaphosphaheterocycles. They have been prepared through two major strategies of cyclizations and annulations. Cyclizations achieve ring construction through the formation of any bond in the ring, while annulations build the ring via [4 + 1] and [3 + 2] fashions with the simultaneous formation of two bonds. The review includes the synthesis of 1,2-azaphospholidine and 1,2-azaphospholine 2-oxides/sulfides and their fused derivatives.
Collapse
Affiliation(s)
- Jiaxi Xu
- State Key Laboratory of Chemical Resource Engineering, Department of Organic Chemistry, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China
- College of Sciences, Henan Agricultural University, Zhengzhou 450002, People’s Republic of China
| |
Collapse
|
2
|
Reis SG, Del Águila-Sánchez MA, Guedes GP, Ferreira GB, Novak MA, Speziali NL, López-Ortiz F, Vaz MGF. Synthesis, crystal structures and magnetic behaviour of four coordination compounds constructed with a phosphinic amide-TEMPO radical and [M(hfac)2] (M = Cu(II), Co(II) and Mn(II)). Dalton Trans 2014; 43:14889-901. [PMID: 25177845 DOI: 10.1039/c4dt01444h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In the present work we describe the synthesis, crystal structures and magnetic properties of four coordination compounds obtained by assembling a new phosphinic amide containing the TEMPO moiety, 1-piperidinyloxy-4-[(diphenylphosphinyl)amino]-2,2,6,6-tetramethyl radical (dppnTEMPO), with [M(hfac)2] building blocks (M = Cu(II), Co(II), Mn(II)). The crystal structures of the coordination compounds revealed the usefulness of the functionalized radical to provide discrete or extended architectures. In the copper compound () the ligand is coordinated through the oxygen atom of the NP[double bond, length as m-dash]O linkage to the metal, which exists in a square pyramidal or octahedral geometry. For the cobalt and manganese complexes (), both the phosphinic amide and the nitroxide oxygen atoms are involved in the coordination to the metal leading to one dimensional systems. In the cobalt complex () an interesting spin topology in the zig-zag chain was obtained due to the oxygen atom of the phosphinic amide group being μ2 coordinated to two cobalt(ii) ions. The magnetic behaviour of the coordination compounds shows overall antiferromagnetic interactions involving the metal ion and the organic radical. DFT calculations were performed in order to assign the main path for the magnetic interactions.
Collapse
Affiliation(s)
- Samira G Reis
- Instituto de Química, Universidade Federal Fluminense, 24020-141 Niterói, RJ, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|
3
|
Dearomatizing anionic cyclization of N-methyl-N-benzyldi(1-naphthyl)phosphinamide: a route for access to a new class of functionalized tricyclic azaphospholes with antitumor properties. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.11.094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
4
|
Ruiz-Gómez G, Francesch A, José Iglesias M, López-Ortiz F, Cuevas C, Serrano-Ruiz M. Dearomatizing Anionic Cyclization of Phosphonamides. A Route to Phosphonic Acid Derivatives with Antitumor Properties. Org Lett 2008; 10:3981-4. [DOI: 10.1021/ol801463g] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gloria Ruiz-Gómez
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain, PharmaMar S.A., Av. de los Reyes, 1, P.I. La Mina, 28770, Colmenar Viejo, Madrid, Spain, and Área de Química Inorgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| | - Andrés Francesch
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain, PharmaMar S.A., Av. de los Reyes, 1, P.I. La Mina, 28770, Colmenar Viejo, Madrid, Spain, and Área de Química Inorgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| | - María José Iglesias
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain, PharmaMar S.A., Av. de los Reyes, 1, P.I. La Mina, 28770, Colmenar Viejo, Madrid, Spain, and Área de Química Inorgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| | - Fernando López-Ortiz
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain, PharmaMar S.A., Av. de los Reyes, 1, P.I. La Mina, 28770, Colmenar Viejo, Madrid, Spain, and Área de Química Inorgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| | - Carmen Cuevas
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain, PharmaMar S.A., Av. de los Reyes, 1, P.I. La Mina, 28770, Colmenar Viejo, Madrid, Spain, and Área de Química Inorgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| | - Manuel Serrano-Ruiz
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain, PharmaMar S.A., Av. de los Reyes, 1, P.I. La Mina, 28770, Colmenar Viejo, Madrid, Spain, and Área de Química Inorgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| |
Collapse
|
5
|
Oña-Burgos P, Fernández I, Roces L, Torre-Fernández L, García-Granda S, López-Ortiz F. Asymmetric Deprotonation−Substitution of N-Pop-benzylamines Using [RLi/(−)-Sparteine]. Enantioselective Sequential Reactions and Synthesis of N-Heterocycles. Org Lett 2008; 10:3195-8. [DOI: 10.1021/ol801027p] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pascual Oña-Burgos
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Ignacio Fernández
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Laura Roces
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Laura Torre-Fernández
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Santiago García-Granda
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Fernando López-Ortiz
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| |
Collapse
|
6
|
Oña Burgos P, Fernández I, Iglesias MJ, García-Granda S, López Ortiz F. Phosphinamide-Directed Benzylic Lithiation. Application to the Synthesis of Peptide Building Blocks. Org Lett 2008; 10:537-40. [DOI: 10.1021/ol7028096] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pascual Oña Burgos
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería 8, 33006 Oviedo, Spain
| | - Ignacio Fernández
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería 8, 33006 Oviedo, Spain
| | - María José Iglesias
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería 8, 33006 Oviedo, Spain
| | - Santiago García-Granda
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería 8, 33006 Oviedo, Spain
| | - Fernando López Ortiz
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/Julián Clavería 8, 33006 Oviedo, Spain
| |
Collapse
|
7
|
Ruiz-Gómez G, Iglesias MJ, Serrano-Ruiz M, López-Ortiz F. Dearomatizing anionic cyclization of N-alkyl-N-benzyl(dinaphthyl)phosphinamides. A facile route to gamma-(amino)dihydronaphthalenylphosphinic acids. J Org Chem 2007; 72:9704-12. [PMID: 17979287 DOI: 10.1021/jo701607s] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dearomatizing anionic cyclization of N-alkyl-N-benzyldi(n-naphthyl)phosphinamides (n = 1, 2) and subsequent trapping with a series of electrophiles (MeOH, MeI, CF3SO3Me, Me3O+BF4-, AllylBr, and PhCH2Br) have been accomplished. Optimized reaction conditions (base, temperature, reaction time) allow for synthesizing tetrahydro-1H-naphtho[1,2-c][1,2]-azaphosphole 1-oxides 13 and 18 and tetrahydro-1H-naphtho[2,1-c][1,2]azaphosphole 3-oxides 16 and 27-29 in high yield and diastereoselectivity. Appropriate selection of the base proved to be critical for promoting anionic cyclization of 2-naphthyl derivatives. The dearomatized heterocycles are transformed quantitatively into gamma-(N-alkylamino)phosphinic acids by acid hydrolysis of the P-N linkage. Bioactivity assays on five human tumor cell lines for one of these amino acids revealed growth inhibition factors (GI50) at a micromolar scale. Additionally, evidence for the feasibility of intermolecular nucleophilic dearomatization and sequential nucleophilic attack to both aromatic rings of dinaphthylphosphinamides have been obtained.
Collapse
Affiliation(s)
- Gloria Ruiz-Gómez
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain
| | | | | | | |
Collapse
|
8
|
Ortiz FL, Iglesias MJ, Fernandez I, Sanchez CMA, Gómez GR. Nucleophilic Dearomatizing (DNAr) Reactions of Aromatic C,H-Systems. A Mature Paradigm in Organic Synthesis. Chem Rev 2007; 107:1580-691. [PMID: 17488057 DOI: 10.1021/cr030207l] [Citation(s) in RCA: 266] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fernando López Ortiz
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain.
| | | | | | | | | |
Collapse
|
9
|
Ruiz-Gómez G, Iglesias MJ, Serrano-Ruiz M, García-Granda S, Francesch A, López-Ortiz F, Cuevas C. Double dearomatization of bis(diphenylphosphinamides) through anionic cyclization. A facile route of accessing multifunctional systems with antitumor properties. J Org Chem 2007; 72:3790-9. [PMID: 17439285 DOI: 10.1021/jo070276q] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The sequential one-pot double dearomatization of bis(N-benzyl-P,P-diphenylphosphinamides) via anionic cyclization is described for the first time. Protonation and alkylation of the dearomatized dianions provide bis(tetrahydro-2,1-benzazaphospholes) in good yield and with very high regio- and stereocontrol. Acid-catalyzed methanolysis of the bisheterocycles affords bis(methyl gamma-aminophosphinates) stereospecifically. The doubly phosphorylated systems proved to be active against a series of cancer cell lines.
Collapse
Affiliation(s)
- Gloria Ruiz-Gómez
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain
| | | | | | | | | | | | | |
Collapse
|
10
|
Arnott G, Clayden J, Hamilton SD. Azabicyclic amino acids by stereoselective dearomatizing cyclization of the enolates of N-nicotinoyl glycine derivatives. Org Lett 2007; 8:5325-8. [PMID: 17078709 DOI: 10.1021/ol062126s] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[Structure: see text] On activation by pyridine N-acylation, enolates of N-nicotinoyl and N-isonicotinoyl glycine and alanine derivatives cyclize to yield 6,5-azabicyclic or 6,4-azaspirocyclic lactams. With an N-alpha-methyl-p-methoxybenzyl group the cyclization is diastereoselective; hydrogenation and deprotection yields azabicyclic amino acids in 94:6 er.
Collapse
Affiliation(s)
- Gareth Arnott
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | | | | |
Collapse
|
11
|
Nishiwaki K, Ogawa T, Tagami KI, Tanabe G, Muraoka O, Matsuo K. A new method of constructing dearomatized compounds using triazene. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
12
|
Ramallal AM, Fernández I, López Ortiz F, González J. Mechanism of Anionic Dearomatizing Reactions of Diphenylphosphinamide Derivatives: A Theoretical and Experimental Study. Chemistry 2005; 11:3022-31. [PMID: 15761841 DOI: 10.1002/chem.200400987] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The mechanism of the anionic dearomatisation of phosphinamide derivatives has been investigated both theoretically and experimentally. The potential-energy surface of model reactions was studied at the Becke3LYP/6-31+G* level of theory, and according to this study, a pre-reactive complex is formed between the alkyllithium and the phosphinamide. This complex evolves preferentially through NC(alpha)-metalation of the phosphinamide. The intramolecular nucleophilic addition of the carbanion to the ortho position of the aromatic ring leads to the dearomatised products, in a reaction that has been shown to be under thermodynamic control. Coordinating co-solvents, such as hexamethyl phosphoramide (HMPA) or N,N'-dimethyl-N,N'-propylene urea (DMPU), appear to influence the reaction by favouring the formation of solvent-separated ion pairs. The cyclisation reaction of allylphosphinamide derivatives was also studied. It was found that both the alpha- and gamma-attack of the allyl anion can take place, however the formation of the seven-membered ring products derived from the gamma-attack are clearly favoured.
Collapse
Affiliation(s)
- Antonio Morán Ramallal
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo c/Julián Clavería 8, 33006 Oviedo, Spain
| | | | | | | |
Collapse
|
13
|
Fernández I, Gómez GR, Alfonso I, Iglesias MJ, Ortiz FL. Unprecedented asymmetric induction through configurationally stable lithium N-(α-methylbenzyl)phosphinamides. A new entry to enantiomerically pure γ-aminophosphinic acids and esters. Chem Commun (Camb) 2005:5408-10. [PMID: 16261229 DOI: 10.1039/b510685k] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first examples of configurationally stable N-benzyl-N-phosphinoyl carbanions are described. Their applications to the synthesis of homochiral gamma-aminophosphinic acids and esters via highly enantioselective dearomatising reactions are shown.
Collapse
Affiliation(s)
- Ignacio Fernández
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120, Almería, Spain
| | | | | | | | | |
Collapse
|
14
|
Fernández I, González J, López-Ortiz F. Deuterium-Labeling and NMR Study of the Dearomatization of N-Alkyl-N-benzyldiphenylphosphinamides through Anionic Cyclization: Ortho and Benzylic Lithiation Directed by Complex-Induced Proximity Effects. J Am Chem Soc 2004; 126:12551-64. [PMID: 15453788 DOI: 10.1021/ja039863t] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mechanism of the anionic cyclization dearomatizing reaction of N-benzyl-N-methyldiphenylphosphinamide (1) upon treatment with s-BuLi in tetrahydrofuran (THF) at -90 degrees C has been analyzed by deuterium-labeling and natural abundance multinuclear magnetic resonance ((1)H, (2)H, (7)Li, (13)C, (31)P) studies. In the absence of coordinating cosolvents such as hexamethylphosphoramide (HMPA), eight major anionic species were identified, which allowed us to unravel the pathway of the metalation reaction. In agreement with the complex-induced proximity effect (CIPE) mechanism, the sequence of transformations emerging from this study involves the coordination of the lithium base to the P=O group of 1 to give four dimeric precomplexes whose NMR data are consistent with structures Va/Vb and VIIIa/VIIIb. The diastereomers Va/Vb are the precursors of the monomeric benzylic anion II, whereas the VIIIa/VIIIb diastereomers are assumed to undergo ortho deprotonation leading to anions I. Translocation from the ortho anion to the benzylic one is not observed. Intramolecular conjugate addition of anion II to the P-phenyl rings happens in a reversible way, affording the monomeric dearomatized anions III, IV, VI, and VII. The reaction progresses to yield a mixture containing only the species I, III, and IV. HMPA acts as a catalyst for the ortho-to-benzylic translocation and anionic cyclization reactions. Two-dimensional (2D) (7)Li,(31)P[(1)H] shift correlations and (7)Li[(31)P] NMR spectra proved to be crucial for the structural assignment of the anionic species. These techniques also demonstrated the diastereotopicity of the two achiral ligands involved in a dimer with s-BuLi (Vb) owing to the slow configuration inversion of the carbanion center.
Collapse
Affiliation(s)
- Ignacio Fernández
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, Almería, Spain
| | | | | |
Collapse
|
15
|
Fernández I, Price RD, Bolton PD, Mahon MF, Davidson MG, López-Ortiz F. X-ray and multinuclear NMR study of the mixed aggregate [(Ph2P(O)N(CH2Ph)CH3)·LiOC6H2-2,6-{C(CH3)3}2-4-CH3)·C7H8]2: a model for the directed metalation of phosphinamides. J Organomet Chem 2004. [DOI: 10.1016/j.jorganchem.2004.03.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
16
|
Ramallal AM, López-Ortiz F, González J. Ionic vs Pericyclic Transition States for the Cyclization Reactions of Cα-N Anions Derived from Amides and Phosphinamides. Org Lett 2004; 6:2141-4. [PMID: 15200305 DOI: 10.1021/ol0493204] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[structure: see text] Ab initio and DFT calculations indicate that the anionic cyclization of vinyl- and phenyl-carboxamides and phosphinamides metalated at the C(alpha)-N carbon fits better to a Michael-type ionic addition than to an electrocyclic ring closure. The lithium atom has no influence on the type of reaction mechanism.
Collapse
Affiliation(s)
- Antonio Morán Ramallal
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, c/Julián Clavería 8, 33006, Oviedo, Spain
| | | | | |
Collapse
|
17
|
Fernández I, Forcén-Acebal A, García-Granda S, López-Ortiz F. Synthesis of functionalized 1,4-cyclohexadienes through intramolecular anionic dearomatization of N-alkyl-N-benzyldiphenylphosphinamides. Insight into the reaction mechanism. J Org Chem 2003; 68:4472-85. [PMID: 12762753 DOI: 10.1021/jo0342370] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A generalization of the intramolecular nucleophilic dearomatization-electrophilic alkylation reactions of N-alkyl-N-benzyldiphenylphosphinamide anions is presented. The process has been optimized by analyzing the effects of metalation and quench times, additives, the nature of the electrophiles used (MeI, CF(3)SO(3)Me, Me(3)O(+)BF(4)(-), AllylBr, PhCH(2)Br, BrCH(2)CO(2)Me, and RCH=O, where R = Ph, 4-Cl-C(6)H(4), 4-MeO-C(6)H(4), and (i)()Pr), and the alkyl substituent linked to the nitrogen of the phosphinamide. Both HMPA and DMPU act as catalysts. The latter proved to be much more efficient for obtaining high yields of substituted tetrahydrobenzo[c][1,2]-1lambda(5)-phospholes containing a 1,4-cyclohexadiene system with very high regio- and diastereoselectivity. Steric effects in the neighborhood of the benzylic anion tend to decrease the stereoselectivity of the anionic cyclization. The optimization study also served to shed light on the reaction mechanism of the dearomatization process by identifying several intermediate species and showing the reversibility of the anionic cyclization step as well as of the reaction with aldehydes.
Collapse
Affiliation(s)
- Ignacio Fernández
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento, Spain
| | | | | | | |
Collapse
|
18
|
Andújar Sánchez CM, Iglesias MJ, López Ortiz F. Synthesis of functionalised cyclohexadienes through addition of lithiated phosphine borane complexes to benzonitriles. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)02406-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
19
|
Fernández I, Ortiz FL, Velázquez AM, Granda SG. Regio- and diastereoselective preparation of tetrahydrobenzo[c]-1-aza-2lambda(5)-phospholes through dearomatization cyclization of lithiated N-benzyl-N-alkyl(diphenyl)phosphinamides. Synthesis of gamma-(N-alkylamino)phosphinic acids. J Org Chem 2002; 67:3852-60. [PMID: 12027703 DOI: 10.1021/jo025587+] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A study of the protonation of the cycloadducts derived from the dearomatization reaction of lithiated N-alkyl-N-benzyldiphenylphosphinamides has been carried out. The regio- and stereoselectivity of the process has been analyzed in terms of the size of the N-alkyl substituent, the acidity and size of the protonating reagent, and the cosolvent used. The optimization of these variables allowed the preparation of tetrahydrobenzo[c]-1-aza-2lambda(5)-phospholes containing a 1,3-cyclohexadiene or 1,4-cyclohexadiene system with moderate to excellent regio- and stereocontrol. The heterocycles were readily hydrolyzed, affording gamma-(N-alkylamino)diphenylphosphinic acids with the functionalities linked to a cyclohexadiene substructure.
Collapse
Affiliation(s)
- Ignacio Fernández
- Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento, 04120 Almería, Spain
| | | | | | | |
Collapse
|
20
|
Clayden J, Purewal S, Helliwell M, Mantell SJ. Dearomatizing disrotatory electrocyclic ring closure of lithiated N-benzoyloxazolidines. Angew Chem Int Ed Engl 2002; 41:1049-51. [PMID: 12491309 DOI: 10.1002/1521-3773(20020315)41:6<1049::aid-anie1049>3.0.co;2-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jonathan Clayden
- Department of Chemistry, University of Manchester, Oxford Rd, Manchester M13 9PL, UK.
| | | | | | | |
Collapse
|
21
|
Clayden J, Purewal S, Helliwell M, Mantell SJ. Dearomatizing Disrotatory Electrocyclic Ring Closure of LithiatedN-Benzoyloxazolidines. Angew Chem Int Ed Engl 2002. [DOI: 10.1002/1521-3757(20020315)114:6<1091::aid-ange1091>3.0.co;2-r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
22
|
Mealy MJ, Bailey WF. Synthesis of heterocycles by cyclization of unsaturated organolithiums: a review. J Organomet Chem 2002. [DOI: 10.1016/s0022-328x(01)01244-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
23
|
Regio- and Stereoselective Addition Reactions of Organolithiums. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1460-1567(02)80038-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
|