Intramolecular Michael Addition of N- and O-Centred Nucleophiles to Tethered Acrylates. The Role of Double-Bond Geometry in Controlling the Diastereo- selectivity of Cyclizations Leading to 2,6-Disubstituted Tetrahydropyrans and Piperidines.
d5-Reactions of Doubly Deprotonated ?,?-Unsaturated Carbonyl Derivatives with Electrophiles. A Novel Approach to the Synthesis of Tetrahydrofuran and Tetrahydropyran Derivatives
作者:Dieter Seebach、Manat Pohmakotr、Christian Schregenberger、Beat Weidmann、Raghao S. Mali、Srisuke Pohmakotr
DOI:10.1002/hlca.19820650202
日期:1982.3.17
tested (alkyl halide, silyl chloride, ester, ketone, aldehyde, epoxide) to give β, γ-unsaturated carbonyl compounds of type A (see Formulae2–6, 13, 14 and Tables 1–5). The α- and β-hydroxyalkylation products obtained from 1a–1d can be converted to tetra-hydrofuran and tetrahydropyran derivatives 7 and 16, respectively (Tables 1 and 2), those from the sulfur analogues 1e and 1f to ketene thioacetals
(+)-(S,S)-(cis-6-Methyltetrahydropyran-2-yl)aceticacid, a constituent of the glandular secretion from the civet cat was synthesized enantiospecifically from (+)-(R,R)-diethyl tartrate via stereospecific reductive ring opening of an optically active 5,7-disubstituted 6,8-dioxabicyclo[3.2.1]octane derivative.
Synthesis of 1,3-dioxin-4-ones having chiral hydroxyalkyl groups at the 6-position by means of baker's yeast reduction and their uses for epc synthesis
Prochiral methyl ketones connected with 6-(4-oxo-1,3-dioxinyl) group directly or through methylene chain (1-3) gave, by treatment with fermenting baker's yeast, the corresponding (S)-alcohols which served as synthons for a variety of enantiomerically pure compounds.
Simple synthesis of (S)-parasorbic acid and other (5S)-hydroxy six-carbon synthons from L-rhamnose
作者:Frieder W. Lichtenthaler、Franz D. Klinger、Pan Jarglis
DOI:10.1016/0008-6215(84)85235-0
日期:1984.9
Intramolecular alkoxypalladation/carbonylation of alkenes