Montmorillonite clay-catalyzed hetero-Diels–Alder reaction of 2,3-dimethyl-1,3-butadiene with benzaldehydes
作者:Matthew R. Dintzner、Andrew J. Little、Massimo Pacilli、Dominic J. Pileggi、Zachary R. Osner、Thomas W. Lyons
DOI:10.1016/j.tetlet.2007.01.010
日期:2007.2
Montmorillonite K10 clay was found to catalyze the hetero-Diels-Alder reaction of 2,3-dimethyl-1,3-butadiene with o-anisaldehyde and other benzaldehyde derivatives; a transition state involving chelation of the clay's metal ions with the dienophile's heteroatoms is proposed. (c) 2007 Elsevier Ltd. All rights reserved.
Carbocation Catalysis: Oxa-Diels-Alder Reactions of Unactivated Aldehydes and Simple Dienes
作者:Mahmoud Abd El Aleem Ali Ali El Remaily、Veluru Ramesh Naidu、Shengjun Ni、Johan Franzén
DOI:10.1002/ejoc.201501112
日期:2015.10
organocatalyst is demonstrated in the oxa-Diels-Alder reaction of various unactivated aromatic and aliphatic aldehydes and simple unactivated dienes, such as isoprene and 2,3-dimethylbutadiene. The transformation proceeds smoothly to give 3,6-dihydropyrane adducts in high to moderate yields with catalyst loadings down to 1.0 mol-% under mild reaction conditions. In contrast to most previously reported