Synthesis of Conformationally Constrained Spirohydantoins with a Dibenzo[a,d]heptadiene Ring
作者:Bin Tao、Jack W. Timberlake
DOI:10.1055/s-2000-7108
日期:——
Conformationally constrained dibenzo[a,d]cycloheptadiene-based spirohydantoins were prepared from dibenzosuberone via the transformation of the α-hydroxy ester to the azido ester, followed by its reduction to the amino ester, and cyclization of the carbomethoxy N,N′-asymmetric ureas, derived from the amino ester with triphosgene and a variety of amines. A novel ring expansion reaction was also observed in the process.
通过将δ-羟基酯转化为叠氮基酯,然后将其还原为氨基酯,再将氨基酯与三苯并庚烯和多种胺环化,制备出了构象受限的二苯并[a,d]环庚二烯基螺海因。在此过程中还观察到了一种新的扩环反应。