Thiourea-Catalyzed Enantioselective Hydrophosphonylation of Imines: Practical Access to Enantiomerically Enriched α-Amino Phosphonic Acids
摘要:
Chiral thiourea 1b catalyzes the highly enantioselective hydrophosphonylation of a wide range of N-benzyl imines. The hydrophosphonylation products are readily deprotected by hydrogenolysis, providing access to free alpha-amino phosphonic acids in highly enantioenriched form.
A New and Convenient Asymmetric Synthesis of α-Amino- and α-Alkyl-α-aminophosphonic Acids Using <i>N</i>-<i>tert</i>-Butylsulfinyl Imines as Chiral Auxiliaries
作者:Chengye Yuan、Qianyi Chen
DOI:10.1055/s-2007-990872
日期:2007.12
successfully at room temperature with potassium carbonate as base to afford α-amino- and α-alkyl-α-amino- N-( TERT-butylsulfinyl)phosphonates in good to excellent chemical yield and diastereoselectivity. The major diastereo-mers were separated and smoothly converted into enantiopure α-amino- and α-alkyl-α-aminophosphonic acids.
Straightforward Synthesis of Depsiphosphonopeptides via Mannich-Type Multicomponent Condensation
作者:Jiaxi Xu、Yuanhe Gao
DOI:10.1055/s-2006-926324
日期:——
A straightforward method for the synthesis of depsiphosphonopeptides via a Mannich-type multicomponent condensation of simple starting materials, such as benzyl carbamate, aldehydes, and 1-carbethoxyalkyl phosphorodichloridites, was developed. Compared to previous methods, our strategy provides a more efficient, convenient, and practical route for the preparation of depsiphosphonopeptides under mild reaction conditions with good yields. Such a strategy avoids the initial synthesis of 1-aminoalkylphosphonic acid or 1-aminoalkylphosphonous acid derivatives as starting materials.
A new synthesis of chiral α- and β-aminophosphonic acids is described which involves a highly diastereoselective addition of phosphite and phosphonate anions to enantiopure sulfinimines.
Highly Enantioselective Conjugate Additions of Phosphites to α,β-Unsaturated<i>N</i>-Acylpyrroles and Imines: A Practical Approach to Enantiomerically Enriched Amino Phosphonates
作者:Depeng Zhao、Yuan Wang、Lijuan Mao、Rui Wang
DOI:10.1002/chem.200901901
日期:2009.10.19
The first highlyenantioselective phosphonylation of α,β‐unsaturated N‐acylpyrroles has been developed. Excellent yields (91–99 %) and enantioselectivities (up to >99 % enantiomeric excess (ee)) were observed for a broad spectrum of both phosphites and N‐acylpyrroles under mild conditions. In particular, when diethyl phosphite was employed to test the scope of the N‐acylpyrroles, almost optically pure
Stereoselective Addition of Dimethyl Thiophosphite to Imines
作者:Pakamas Tongcharoensirikul、Alirica I. Suarez、Troy Voelker、Charles M. Thompson
DOI:10.1021/jo035707t
日期:2004.4.1
benzaldimine derived from threonine methyl ester and alanine methyl ester were far less diastereoselective, affording 38:62 and 61:39 ratios, respectively. Addition of DMTP to the benzaldimine derived from (R)-α-methylbenzylamine (78:22) and (S)-serine methyl ester (73:27) were intermediate in selectivity. DMTP addition to the imines formed between serine methyl ester and acetaldehyde and isobutyraldehyde