4173-41-5Relevant articles and documents
Synthesis of α,β-Unsaturated Acylsilanes via Perrhenate-Catalyzed Meyer-Schuster Rearrangement of 1-Silylalkyn-3-ols
Nikolaev, Andrei,Orellana, Arturo
, p. 5796 - 5799 (2015)
We report the synthesis of α,β-unsaturated acylsilanes via the perrhenate-catalyzed Meyer-Schuster rearrangement of 1-silylalkyn-3-ols. Propargylic alcohols derived from TES-acetylene and substituted benzaldehydes can be converted to acylsilanes using a c
Total syntheses of the gregatins A-D and aspertetronin A: Structure revisions of these compounds and of aspertetronin B, together with plausible structure revisions of gregatin E, cyclogregatin, graminin A, the penicilliols A and B, and the huaspenones A and B
Burghart-Stoll, Heike,Brueckner, Reinhard
supporting information; experimental part, p. 3978 - 4017 (2012/10/18)
Comprehensive comparisons of 1H and 13C NMR chemical shift values in the furanone cores a, b, and c provide plausible support for a reassessment of the furanone nuclei of the title compounds from b to c. Total syntheses via enantiomerically pure lactic esters were based on the Seebach-Frater "self-reproduction of stereocenters" methodology. Attachment of the hexadienyl side-chain in a trans,trans-selective manner was achieved by addition of the Seebach-Frater enolate to trans-hex-4-en-1-al rather than to trans-hex-3-en-1-al. The type-c furanone cores of the synthetic materials were reached by single or double acylation of a model γ-hydroxy-β-oxo ester (compound 50) and its hexadiene-containing counterpart 29. Our syntheses confirmed the novel connectivities in six compounds. In addition, they required revision of the configuration of a quaternary carbon atom in five cases. Moreover, they allowed elucidation of the configurations of four previously unassigned stereocenters. Hindsight analyses of why the furanone cores of the title compounds had been misinterpreted as a and/or b instead of c are given. Why the stereocenters in the heterocycles had been incorrectly configured, on the bases (a) of relay studies in the 1960s, and (b) of a 1984 total synthesis of gregatin B, is also discussed.
Highly Stereoselective Isomerization of Ynones to Conjugated Dienones Catalyzed by Transition-Metal Complexes
Ma, Dawei,Yu, Yihua,Lu, Xiyan
, p. 1105 - 1109 (2007/10/02)
α,β-Ynones isomerize in the presence of a catalytic amount of IrH5(i-Pr3P)2, RuH2(Ph3P)4-Bu3P, or RuCl2(Ph3P)3-Ph3P in benzene at 35-80 deg C to give (E,E)-α,β:γ,δ-dienones in high yield with high stereoselectivity.This experimentally simple and economica
