Allylic sulfides were synthesized from allylic alcohols 1 using S, S'-bis(1-phenyl-1H-tetrazol-5-yl) dithiocarbonate (2) by means of a single-step reaction. The allylic sulfides were coupled with a Grignard reagent or carbanion in the presence of a catalytic amount of copper(I) bromide or palladium(0).
Regio-controlled Prenylation and Geranylation of 3-Furylmethylmagnesium Bromide. Selective Syntheses of 3-Substituted Furanoid and 2-Substituted 3-Methylfuranoid Terpenes
作者:Shuki Araki、Yasuo Butsugan
DOI:10.1246/bcsj.56.1446
日期:1983.5
main products. When the reactions were carried out in the presence of a catalytic amount of copper(I) iodide, normal coupling occurred and 3-substituted furans, perillene and dendrolasin, were formed in good yields. The related naturally occurring 3-substitutedthiophene, 3-(4-methyl-3-pentenyl)thiophene, was also synthesized from 3-thienylmethylmagnesium bromide and prenyl diethy phosphate.
Annulated heterocycles through a radical-cation cyclization: synthetic and mechanistic studies
作者:Jeffrey B. Sperry、Dennis L. Wright
DOI:10.1016/j.tet.2006.03.058
日期:2006.7
and thiophenes, especially reactions leading to dearomatization of the nucleus, make them highly versatile synthons for complex molecule construction. As part of a program to exploit this intrinsic reactivity, we have developed a convenient method to prepare annulated versions of these heterocycles. The strategy is based on a two-step annulation involving the initial conjugate addition of a heteroaryl
Total syntheses of the labdane diterpene lactones marrubiin, marrulibacetal, desertine, marrulibacetal A, marrubasch F, cyllenine C, marrulanic acid, and marrulactone are described. The trans-decalin moiety of these molecules was constructed in a stereoselective manner by a Pauson-Khand reaction, and the resultant cyclopentenone was oxidatively cleaved for formation of the lactone ring. Elongation
SELECTIVE SYNTHESES OF DENDROLASIN AND SESQUIROSEFURAN BY THE COUPLING OF 3-FURYLMETHYLMAGNESIUM BROMIDE WITH GERANYL DIETHYL PHOSPHATE
作者:Shuki Araki、Yasuo Butsugan
DOI:10.1246/cl.1982.177
日期:1982.2.5
Coupling reaction of 3-furylmethylmagnesium bromide with geranyl diethyl phosphate in the presence and the absence of copper(I) iodide affords dendrolasin and sesquirosefuran, respectively, in ca. 80 % selectivity.