Facile Condensation of Aromatic Aldehydes with Chroman-4-ones and 1-Thiochroman-4-ones Catalysed by Amberlyst-15 under Microwave Irradiation Condition
作者:Tapas K. Mandal、Rammohan Pal、Rina Mondal、Asok K. Mallik
DOI:10.1155/2011/426560
日期:——
Different aromatic aldehydes and cinnamaldehyde undergo cross-aldol condensation with chroman-4-ones and1-thiochroman-4-ones in the presence of amberlyst-15 under microwave irradiation in solvent free condition to afford rapidly the correspondingE-3-arylidene andE-3-cinnamylidene derivatives, respectively, in high yield. This process is simple, efficient and environmentally benign.
Highly efficient construction of spirocyclic chromanone–pyrrolidines via Cu(i)/TF–BiphamPhos-catalyzed asymmetric 1,3-dipolar cycloaddition
作者:Tang-Lin Liu、Zhao-Lin He、Chun-Jiang Wang
DOI:10.1039/c1cc13554f
日期:——
A facile synthesis of highly functional spiro-[4-chromanone-3,3â²-pyrrolidine] bearing one unique spiro quarternary and three tertiary stereogenic centers is developed in excellent stereoselectivity for the first time.
that this cycloaddition is regio- and stereoselective affording trans- and cis- spiro-1-pyrazolines. Spiro-1-pyrazolines were converted into spiro-2-pyrazolines on acid-catalysed isomerization. Conformation and relative configuration of compounds prepared has been elucidated by various one- and two-dimensional n.m.r. methods.