Dimethyl sulfide–boron trihalide-mediated reactions of α,β-unsaturated ketones with aldehydes: one-pot synthesis of Baylis–Hillman adducts and α-halomethyl enones
作者:Tatsunori Iwamura、Masaru Fujita、Tetsuya Kawakita、Sayaka Kinoshita、Shin-ichi Watanabe、Tadashi Kataoka
DOI:10.1016/s0040-4020(01)00842-0
日期:2001.10
The reactions of aldehydes with 3-buten-2-one (2) were conducted in the presence of (BBr3Me2S)-Me-. or BCl3-Me2S and then worked up with aqueous NaHCO3, affording the a-methylene aldol 3, (alpha -halomethyl aldol 4 or 6, and a-halomethyl enones 5 or 7, respectively. In contrast, the reactions quenched with water gave the alpha -halomethyl enones 5 or 7 in high yields, while the work-up with an aqueous 10% trimethylamine gave the alpha -methylene aldol 3. The phenol 15 and half-acetal 16 were obtained from the reaction of p-nitrobenzaldehyde (1a) with cyclohexenone (10). (C) 2001 Elsevier Science Ltd. All rights reserved.