Heteropolyacid-Catalyzed Direct Deoxygenation of Propargyl and Allyl Alcohols
摘要:
The combination of H-3[PW12O40]center dot nH(2)O (1 mol %) and Et3SiH led to the direct catalytic deoxygenation of propargyl alcohols, in which proper solvent selection Cl(CH2)(2)Cl vs CF3CH2OH was the key to obtaining better product yields. Under similar conditions, the deoxygenation of allyl alcohols proceeded to give thermodynamically stable alkenes with migration of the double bonds in good yields.
Highly enantioselective addition of linear alkyl alkynes to aromatic aldehydes
摘要:
An asymmetric linear alkyl alkyne addition to aromatic aldehydes catalyzed by the Ti-(R)-BINOL system is reported with high enantioselectivity and yield. Our study expands upon the synthetic scope of propargylic alcohols, which could serve as potentially useful intermediates for the synthesis of various natural products. (C) 2011 Elsevier Ltd. All rights reserved.