55109-55-2Relevant academic research and scientific papers
Trimerization of aliphatic aldehydes to 1,3-diol monoesters catalyzed by Cp*2Sm(thf)2
Miyano, Akira,Tashiro, Daisuke,Kawasaki, Yumi,Sakaguchi, Satoshi,Ishii, Yasutaka
, p. 6901 - 6902 (1998)
Aliphatic aldehydes underwent trimerization in the presence of a catalytic amount of Cp*2Sm(thf)2 under ambient conditions to form 1,3- diol monoestcrs in good yields. For example, the reaction of acetoaldehyde catalyzed by Cp*2Sm(thf)2 gave 4-acetoxy-2-butanol (2a) and 3-acetoxy-1- butanol (3a) in 86% yield.
Metal-Organic Frameworks Invert Molecular Reactivity: Lewis Acidic Phosphonium Zwitterions Catalyze the Aldol-Tishchenko Reaction
Bauer, Gerald,Ongari, Daniele,Xu, Xiaoying,Tiana, Davide,Smit, Berend,Ranocchiari, Marco
supporting information, p. 18166 - 18169 (2017/12/27)
The influence of metal-organic frameworks (MOFs) as additives is herein described for the reaction of n-alkyl aldehydes in the presence of methylvinylketone and triphenylphosphine. In the absence of a MOF, the expected Morita-Baylis-Hillman product, a β-hydroxy enone, is observed. In the presence of MOFs with UMCM-1 and MOF-5 topologies, the reaction is selective to Aldol-Tishchenko products, the 1 and 3 n-alkylesters of 2-alkyl-1,3-diols, which is unprecedented in organocatalysis. The (3-oxo-2-butenyl)triphenylphosphonium zwitterion, a commonly known nucleophile, is identified as the catalytic active species. This zwitterion favors nucleophilic character in solution, whereas once confined within the framework, it becomes an electrophile yielding Aldol-Tishchenko selectivity. Computational investigations reveal a structural change in the phosphonium moiety induced by the steric confinement of the framework that makes it accessible and an electrophile.
