Ring Closing Metathesis for the Asymmetric Synthesis of (S)-Homopipecolic Acid, (S)-Homoproline and (S)-Coniine
作者:Stephen G. Davies、Keiji Iwamoto、Christian A. P. Smethurst、Andrew D. Smith、Humberto Rodriguez-Solla
DOI:10.1055/s-2002-32580
日期:——
Diastereoselective conjugate addition of lithium (S)-N-allyl-N-α-methylbenzylamide to α,β-unsaturated esters or Weinreb amides, followed by ring closing metathesis is used to afford the cyclic β-amino acids (S)-homopipecolic acid and (S)-homoproline and the amine (S)-coniine in high ee.
Diastereoselective Ireland–Claisen rearrangements of substituted allyl β-amino esters: applications in the asymmetric synthesis of C(5)-substituted transpentacins
作者:Stephen G. Davies、Ai M. Fletcher、James A. Lee、Paul M. Roberts、Myriam Y. Souleymanou、James E. Thomson、Charlotte M. Zammit
DOI:10.1039/c4ob00274a
日期:——
The diastereoselective Ireland–Claisen rearrangement of a range of substituted allyl β-amino esters gave the corresponding enantiopure α-substituted-β-amino esters with good diastereoselectivity. The application of this methodology in the asymmetric synthesis of a range of C(5)-substituted 1,2-anti-1,5-syn-transpentacins was demonstrated by the rearrangement of a range of β-amino esters derived from
Asymmetric Synthesis of the Tetraponerine Alkaloids
作者:Stephen G. Davies、Ai M. Fletcher、Ian T. T. Houlsby、Paul M. Roberts、James E. Thomson
DOI:10.1021/acs.joc.7b00837
日期:2017.7.7
The asymmetric syntheses of all eight tetraponerine alkaloids (T1–T8) were achieved using the diastereoselective conjugate additions of lithium amide reagents in the key stereodefining steps. Conjugate addition of either lithium (R)-N-allyl-N-(α-methylbenzyl)amide or lithium (R)-N-(but-3-en-1-yl)-N-(α-methylbenzyl)amide to tert-butyl sorbate was followed by ring-closing metathesis of the resultant
Asymmetric synthesis of cyclic β-amino acids and cyclic amines via sequential diastereoselective conjugate addition and ring closing metathesis
作者:Ann M Chippindale、Stephen G Davies、Keiji Iwamoto、Richard M Parkin、Christian A.P Smethurst、Andrew D Smith、Humberto Rodriguez-Solla
DOI:10.1016/s0040-4020(03)00411-3
日期:2003.4
β-unsaturated esters followed by ringclosingmetathesis is used to afford efficiently a range of substituted cyclic β-amino esters in high d.e. Alternatively, conjugate addition to α,β-unsaturated Weinreb amides, functional group conversion and ringclosingmetathesis affords cyclic amines in high d.e. The further application of this methodology to the synthesis of a range of carbocyclic β-amino esters via
Asymmetric Conjugate Additions of Chiral Phosphonamide Anions to α,β-Unsaturated Carbonyl Compounds. A Versatile Method for Vicinally Substituted Chirons
作者:Stephen Hanessian、Arthur Gomtsyan、Nadia Malek
DOI:10.1021/jo000388g
日期:2000.9.1
Reactions of anions derived from chiral nonracemic allyl, crotyl, and cinnamyl bicyclic C(2)-symmetrical phosphonamides with alpha, beta-unsaturated cyclic ketones, esters, lactones, and lactams take place at the gamma-position of the reagents. The products are diastereomerically pure or enriched beta-substituted carbonylcompounds. The method also provides easy access to vicinal substitution of as