The invention describes a process for stabilizing an organic material against oxidative, thermal or light-induced degradation, which comprises incorporating therein or applying thereto at least a compound of the formula (I) wherein the general symbols are as defined in claim
1
. The compounds of the formula I are especially useful as processing stabilizers for synthetic polymers.
Three-component coupling using arynes and DMF: straightforward access to coumarins via ortho-quinone methides
作者:Hiroto Yoshida、Yu Ito、Joji Ohshita
DOI:10.1039/c1cc11955a
日期:——
ortho-Quinone methides, arising from a formal [2+2] cycloaddition between arynes and DMF, were found to facilely undergo a [4+2] cycloaddition with ester enolates or ketenimine anions to produce diverse coumarins in a straightforward manner.