Baylis–Hillman reaction under solvent-free conditions — Remarkable rate acceleration and yield enhancement

Abstract

A simple and efficient method has been developed for remarkable rate acceleration and yield enhancement of the Baylis–Hillman reaction under solvent-free “neat conditions” and solvent-less isolation of products. Reaction of equimolar quantities of aldehyde and olefin in the presence of 20 mol% of DABCO under neat conditions affords the highest yield in most cases within the shortest reaction time, giving support to the mechanisms of proton transfer in protic and aprotic solvents. Solvent-free conditions are found to be especially fast, selective, and high yielding for aromatic aldehydes.

Palladium Catalyzed Annulation of Morita‐Baylis‐Hillman Adducts: Synthesis of Indene and Indanone Derivatives

“…Our studies commenced with the synthesis of Baylis‐Hillman adducts from corresponding aldehydes and acrylates by following literature procedure . Inspired by a previous report, our studies commenced with the reaction of MBH adduct 1 a with 5 mol % of Pd(OAc) 2 , 20 mol % of P(Ph 3 ) 3 , and K 2 CO 3 (2 eq.)…”

Synthesis of Aryl‐(E)‐2‐(azidomethyl)alkenoate and Aryl‐(Z)‐2‐(azidomethyl)acrylonitrile from Aryl Aldehydes and Activated Alkenes via One‐Pot Way

“…Among Baylis–Hillman reaction conditions considered, solvent‐free condition developed by Indian chemist was found to be the best. However, 3 equiv of methyl acrylate and 1 equiv of 1,4‐diazabicyclo[2,2,2]octane (DABCO) rather than a catalytic amount of DABCO and 1 equiv of acrylate are necessary for the completion of the reaction within the reasonable reaction time.…”

Facile Synthesis of Dihydroquinolines via Palladium Catalyzed Sequential Amination and Cyclisation of Morita‐Baylis‐Hillman Alcohols

“…Baylis‐Hillman adducts used in this study are synthesized by following the literature procedure [29] and characterized using spectroscopic analysis. Our present studies commenced with the palladium catalyzed reaction of o ‐bromo substituted Baylis‐Hillman alcohols 1 a with Tosyl amine 2 a .…”