Palladium(0)-catalyzed cyclization-carbonylation of 2,7-octadienyl acetate and homologues
摘要:
The palladium(0)-catalyzed carbonylations, in acetic acid as a necessary solvent, of 2,7-octadienyl acetate and homologues via pi-allylpalladium species were preceded by their intramolecular oelfin insertion to form mixtures of cis/trans-2-vinylcyclopentylacetyl- and cis/trans-cyclohexylacetylpalladium intermediates, which undergo further the intramolecular (5-exo) Heck reaction to give bicyclo-[3.3.0] and [4.3.0] skeletons, respectively, except for one case affording trans-2-vinylcyclopentylacetic acid as a major product.
Enantio- and Diastereoselective Spiroketalization Catalyzed by Chiral Iridium Complex
作者:James Y. Hamilton、Simon L. Rössler、Erick M. Carreira
DOI:10.1021/jacs.7b02856
日期:2017.6.21
complex-catalyzed enantio- and diastereoselective formation of substituted spiroketals from racemic, allylic carbonates is reported, which enables the installation of multiple stereogenic centers in a single operation. The protocol was effective for the preparation of a collection of spiroketals of various ring sizes and substituents, including heteroatoms with high enantio- and diastereoselectivity. Furthermore
The palladium(0)-catalyzed carbonylations, in acetic acid as a necessary solvent, of 2,7-octadienyl acetate and homologues via pi-allylpalladium species were preceded by their intramolecular oelfin insertion to form mixtures of cis/trans-2-vinylcyclopentylacetyl- and cis/trans-cyclohexylacetylpalladium intermediates, which undergo further the intramolecular (5-exo) Heck reaction to give bicyclo-[3.3.0] and [4.3.0] skeletons, respectively, except for one case affording trans-2-vinylcyclopentylacetic acid as a major product.
Synthesis of 2-hydroxybut-3-enylglucosinolate (progoitrin)
作者:Alexander J. MacLeod、John T. Rossiter
DOI:10.1039/p19830000717
日期:——
A synthesis of 2-hydroxybut-3-enylglucosinolate (progoitrin) is described. Its properties and authentication of its biological activity are discussed. This is the first time that this particular glucosinolate has been isolated in pure form by synthesis.