Bismuth Trichloride Catalyzed Efficient Reductive Etherification of Carbonyl Compounds with Alcohols: A Novel Method for Preparation of Symmetrical and Unsymmetrical Ethers
The reductive homocoupling of a carbonylcompound and heterocoupling of a carbonylcompound with a non-protected alcohol were both effected smoothly at room temperature with triethylsilane in the presence of a catalytic amount of bismuth trichloride to afford the corresponding ethers in good yields.
Triflic Acid Catalyzed Reductive Coupling Reactions of Carbonyl Compounds with O-, S-, and N-Nucleophiles
作者:Beate A. Gellert、Nils Kahlcke、Markus Feurer、Stefanie Roth
DOI:10.1002/chem.201101819
日期:2011.10.17
Highly efficient metal‐free reductivecoupling reactions of aldehydes and ketones with a range of nucleophiles in the presence of triflic acid (1–5 mol %) as the catalyst are presented. The reactions can be performed at ambient temperature without exclusion of moisture or air. A range of symmetrical and unsymmetrical ethers were obtained by this method in high yields and short reaction times. For the
The reaction of dialkyl acetals derived from α,β-unsaturated aldehydes with Grignard reagents using TiCl4in THF afforded the cross coupling products, allyl ethers, in high yields. The TiCl4-promotedreaction of alkyl 2,4-dichlorophenyl acetals, synthesized from 3,4-dihydro-2H-pyran or ethyl vinyl ether and 2,4-dichlorophenol, with Grignard reagents in THF at low temperature afforded the corresponding
Reduction of Acetals with TiCl<sub>4</sub>–LiAlH<sub>4</sub>
作者:Hiroshi Ishikawa、Teruaki Mukaiyama
DOI:10.1246/bcsj.51.2059
日期:1978.7
The reduction of dialkyl acetals derived from aromatic aldehydes and ketones with TiCl4–LiAlH4 in THF or diethyl ether at room temperature afforded the coupling products, pinacol ethers or olefins, in high yields. On the other hand, when acetals derived fromaliphaticaldehydes and ketones were treated with TiCl4–LiAlH4 in diethyl ether, the reductive dealkoxylation took place and the corresponding