Efficient Synthesis of Homoallylic Alcohols/Amines from Allyltributylstannane and Carbonyl Compounds/Imines Using Iodine as Catalyst Under Acetic Acid–Water Medium
摘要:
This paper describes a general method for the synthesis of homoallylic alcohols and amines by nucleophilic addition reaction of allyltributylstannane to carbonyl compounds and aldimines where iodine acts as a catalyst in H2O/acetic acid (1:1) medium. Only 10mol% of I-2 is required for various organic transformations. By using this process, various homoallylic alcohols and amines are produced in good to excellent yields.
of α‐methylene‐γ‐lactones through the palladium(II)‐catalyzed lactonization of homoallylic alcohols with alkynamides has been reported. The hydroxyl group in the terminal olefins cooperates with the amide in alkynamides to promote the cyclization by suppressing the β‐H elimination. This process provides a route to construct naturally occurring biologically multifunctional α‐methylene‐γ‐lactones.
The Barbier‐type allylation of aldehydes and ketones can be carried out with both unsubstituted and γ‐substituted allyl bromides using only a catalytic amount (0.1 equiv.) of In metal in [bmim][Br].
SnCl2·2H2O-mediated Barbier-type allylation: A comparative evaluation of the catalytic performance of CuI and Pd(OAc)2
作者:Pabitra Kumar Kalita、Prodeep Phukan
DOI:10.1016/j.crci.2013.02.012
日期:2013.11
Résumé A systematic investigation has been carried out for the allylation of carbonyl compounds under SnCl2·2H2O-mediated Barbier-type conditions, using CuI and Pd(OAc)2 as catalysts. Ketones, which are not reactive under the influence of CuI, however, could be activated by using Pd(OAc)2 as a catalyst. Supplementary Materials: Supplementary material for this article is supplied as a separate file: mmc1.pdf
The indium-catalyzed allylation reaction was performed in good yields and short reaction time with various cyclohexanones in water. Aqueous facial amphiphilic carbohydrates solutions were also screened for their potency to modify the stereochemical outcome of the reaction. (C) 2010 Elsevier Ltd. All rights reserved.
Rapid access to homoallylic alcohols via Pd(OAc)2 catalyzed Barbier type allylation in presence of DMAP
作者:Bishwapran Kashyap、Prodeep Phukan
DOI:10.1016/j.tetlet.2013.09.038
日期:2013.11
DMAP was found to accelerate significantly the rate of Pd(OAc)(2) catalyzed Barbier type allylation of carbonyl compounds by allylbromide using SnCl2 center dot 2H(2)O as reducing agent. Both aldehyde as well as ketones produced excellent yields within a short reaction time in the presence of 3 mol % of Pd(OAc)(2) and 12 mol % of DMAP at room temperature. Aldehydes could be allylated within 5-10 min whereas, in case of ketones, the reaction completes in 45-120 min. (C) 2013 Elsevier Ltd. All rights reserved.