New heterogeneous B(OEt)(3)-MCM-41 catalyst for preparation of alpha,beta-unsaturated alcohols

作者：Uysal Burcu; Oksal Birsen S^*

来源：Research on Chemical Intermediates, 2015, 41(6): 3893-3911.

DOI：10.1007/s11164-013-1498-0

• Mesoporous MCM-41
• Boron tri-ethoxide
• Chemoselectivity
• alpha,beta-Unsaturated aldehydes and ketones
• MPV reduction

Grafting of boron tri-ethoxide on mesoporous MCM-41 resulted in a highly active catalyst for the Meerwein-Ponndorf-Verley (MPV) reduction and the catalyst denoted as B(OEt)(3)-MCM-41. Chemoselective reduction of alpha,beta-unsaturated aldehydes and ketones to the corresponding alpha,beta-unsaturated alcohols was achieved by MPV reduction reaction using a new B(OEt)(3)-MCM-41 catalyst. The prepared new heterogeneous catalyst, B(OEt)(3)-MCM-41, was characterized in detail by using XRD, Si-29 NMR-, B-11 NMR-, C-13 NMR-, and TEM, N-2 adsorption, and ICP-OES. The results demonstrated the successful homogenous distribution of the B(OEt)(3) on the MCM-41 support. The heterogeneous B(OEt)(3)-MCM-41 catalyst, in comparison with the homogeneous B(O (i) Pr)(3) and B(OEt)(3) catalysts, displayed similiar catalytic activity in the MPV reduction of alpha,beta-unsaturated aldehydes and ketones with alcohols as reductants. Reduced reaction times and very high selectivities for the unsaturated alcohols were obtained with the heterogenous catalyst compared with the homogeneous catalysts. The B(OEt)(3)-MCM-41 catalyst was found to be encouraging, as is is recyclable up to six cycles without any significant loss in its catalytic activity.

• 出版日期2015-6