3154-30-1Relevant academic research and scientific papers
Ring-opening cyclization of spirocyclopropanes using sulfoxonium ylides
Onuki, Yuta,Nambu, Hisanori,Yakura, Takayuki
, p. 479 - 486 (2020/09/09)
Ring-opening cyclization of cyclohexane-1,3-dione-2-spirocyclopropanes using dimethylsulfoxonium methylide proceeded regioselectively to produce 2,3,4,6,7,8-hexahydro-5H-1-benzopyran-5-ones in good to high yields. The reactions of cycloheptane- and cyclopentane-1,3-dione-2-spirocyclopropanes could construct [7.6]- and [5.6]-fused ring systems. This reaction was also carried out using sulfoxonium ethylide, butylide, and benzylide, resulting in the formation of the corresponding 2,3-trans-disubstituted products in good to high yields, and it was shown that the dimethyl group can act as a dummy substituent. It was found that the 2- and 3-phenyhexahydrobenzopyran-5-ones can be readily converted into 5-hydroxyflavan and 5-hydroxy-isoflavan, respectively.
Diversity-oriented approach to natural product inspired pyrano-carbazole derivatives: strategic utilization of hetero-Diels-Alder reaction, Fischer indolization and the Suzuki-Miyaura cross-coupling reaction
Kotha, Sambasivarao,Ali, Rashid,Saifuddin, Mohammad
, p. 9003 - 9011 (2015/11/02)
A variety of natural products inspired pyrano-carbazole derivatives have been assembled via hetero-Diels-Alder reaction and Fischer indolization (FI) under operationally simple reaction conditions. Later, the scope of this methodology has been expanded th
Multicomponent reactions of 1,3-cyclohexanediones and formaldehyde in glycerol: Stabilization of paraformaldehyde in glycerol resulted from using dimedone as substrate
Minghao, Li,Chang, Chen,Fei, He,Yanlong, Gua
supporting information; experimental part, p. 519 - 530 (2010/06/13)
Glycerol has proved to be an effective promoting medium for many multicomponent reactions of 1,3-cyclohexanediones and formaldehyde. Styrenes, amines, 2-naphthol, 4-hydroxy-6-methyl-2-pyrone and 4-hydroxy-1-methyl-2- quinolone could easily react with 1,3-cyclohexanediones and paraformaldehyde in glycerol under catalyst-free conditions to afford a variety of complex skeletons in fair to excellent yields. In these reactions, glycerol not only showed a significant promoting effect on the reaction yields but also endowed the reaction system with many typical properties of green chemistry, such as cheap, renewable, recyclable and biodegradable solvent, good safety and easy separation of product. The promoting effect of glycerol for the three-component reaction of styrene, dimedone and paraformaldehyde could be attributed to a restricted formation of the methylene intermediate in glycerol. During the reaction, a physical shell, which is mainly composed of a by-product generated in the beginning of the reaction, might be formed in the surface of paraformaldehyde and plays a key role in controlling the formation of the intermediate by means of restricting the decomposition of paraformaldehyde.
