α-Regioselective construction of gem-bisprenyl structures via zinc-mediated prenylation of esters in THF
摘要:
The in situ generated prenylzinc reagent from the reaction of zinc with prenyl bromide has been shown to undergo a new type of alpha-regioselective addition reaction with a wide range of esters that affords gem-bisprenyl structures. The reaction proceeds under mild conditions to provide alpha,alpha'-adducts with complete alpha-regioselectivity. A mechanism with the consideration of the steric factors is proposed to account for the regioselective results. (C) 2013 Elsevier Ltd. All rights reserved.
The first utility of neodymium as a mediating-metal in the highly [small alpha]-regioselective Barbier reaction of diaryl ketones with allyl halides was reported in this paper. This reaction was conveniently carried...
α-Regioselective Barbier Reaction of Carbonyl Compounds and Allyl Halides Mediated by Praseodymium
作者:San Wu、Ying Li、Songlin Zhang
DOI:10.1021/acs.joc.6b01466
日期:2016.9.2
first utility of praseodymium as a mediating metal in the Barbier reaction of carbonylcompounds with allyl halides was reported in this paper. In contrast to the traditional metal-mediated or catalyzed Barbier reactions, exclusive α-adducts were obtained in this one-pot reaction with a broad scope of substrates and feasible reaction conditions.
Catalytic Enantioselective Epoxidation of Tertiary Allylic and Homoallylic Alcohols
作者:José Luis Olivares-Romero、Zhi Li、Hisashi Yamamoto
DOI:10.1021/ja401182a
日期:2013.3.6
for the enantioselective epoxidation of both tertiary allylic and homoallylicalcoholscatalyzed by Hf(IV)-bishydroxamic acid (BHA) complexes is described. Asymmetric epoxidation, kinetic resolution, and desymmetrization have been developed, demonstrating the flexible nature of the Hf(IV)-BHA system. This is the first report in which these substrates were obtained with enantioselectivities of up to
Photocatalytic Barbier reaction – visible-light induced allylation and benzylation of aldehydes and ketones
作者:Anna Lucia Berger、Karsten Donabauer、Burkhard König
DOI:10.1039/c8sc02038h
日期:——
We report a photocatalytic version of the Barbier type reaction using readily available allyl or benzyl bromides and aromatic aldehydes or ketones as starting materials to generate allylic or benzylic alcohols. The reaction proceeds at room temperature under visible light irradiation with the organic dye 3,7-di(4-biphenyl)1-naphthalene-10-phenoxazine as a photocatalyst and DIPEA as sacrificial electron
Irradiation of aromatic carbonylcompounds and allyl-, 2-methyl-2-propenyl-, or 3-methyl-2-butenyltrimethylstannanes in acetonitrile afforded δ,γ-unsaturated alcohols as major product. A photoinduced electron transfer mechanism is proposed for the allylations.