作者:Gábor Tóth、Áron Szöllősy、Albert Lévai、George Kotovych
DOI:10.1039/p29860001895
日期:——
Spiropyrazolines have been synthesized by 1,3-dipolar cycloaddition of an 2-arylidene-1-tetralone, 3-arylidene-chromanones, -1-thiochromanones, and -flavanones with diazomethane. The relative configuration and stereochemistry of the products have been determined by means of one-dimensional difference N.O.E. measurements. It is shown that ring-closure reaction is regioselective, yielding stereohomogeneous
螺吡唑啉是通过将2-芳基-1-四氢萘酮,3-芳基-苯并二氢呋喃酮,-1-硫代并苯并二氢呋喃酮和-黄烷酮与重氮甲烷进行1,3-偶极环加成而合成的。产品的相对构型和立体化学已经通过一维差异NOE测量来确定。结果表明,闭环反应是区域选择性的,一步产生立体均一的螺并吡唑啉。