letter reports the preparation of quinolines, substituted at the 2- or 3-position by a 4-substituted but-3-en-1-yne group, by the environmentally friendly iron(III)-catalyzed coupling reaction of Grignardreagents with 1-chloro-4-(2-quinolyl)but-1-en-3-yne. The extension and the scope of this non-toxic and chemoselective procedure to various functionalized unsaturated vinyl chlorides are described.
An efficient synthesis of 1,3(E),5(Z), 1,3(E),5(E) and 1,3(Z),5(Z)-trienes: Application to the synthesis of galbanolenes and (9Z,11E)-9,11,13-tetradecatrien-1-yl acetate
The (Pd-Cu)-catalyzed reactions of trimethylsilyl acetylene with (E) or (Z)-chloroenynes, or 1-chloro-(1E,3E)-dienes, followed by desilylation and zinc-reduction of the triple bonds led respectively to (3E,5Z), (3Z,5Z) and (3E,5E)-trienes. Application to the syntheses of galbanolenes and (9Z,11E)-9,11,13-tetradecatrien-1-ylacetate has been realized.
Under palladium or nickel catalysis. a stereomeric mixture 1:1 of (Z) and (E)-1,2-dichloroethylene readily reacts with 1-alkynes. vinyl alanes or vinyl boranes to afford selectively the corresponding (E)-coupling product in good to excellent isolated yields. The selectivity of this coupling reaction is discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.