4-Aryl- and 4-vinyl-2,2-dialkyl-3-chromenes were prepared from tertiary 3-(o-bromophenyl)propynols and aryl iodides or vinyl triflates through a one-pot process, which involves the addition of t-BuONa, dppf and, where appropriate, fresh Pd(OAc)2 to the crude mixture resulting from the hydroarylation or hydrovinylation step [Pd(OAc)2, Et3N, HCOOH, Bu4NCl, toluene]. In general, 4-aryl- and 4-vinyl-2,2-dialkyl-3-chromenes are obtained with high regioselectivity and overall yields range from satisfactory to high. Vinyl triflates tend to give higher yields than aryl iodides.
                                    通过一步法,由叔3-(邻
溴苯基)炔
丙醇和芳基
碘或
乙烯基三氟甲磺酸酯制备了4-芳基和4-
乙烯基-2,2-二烷基-3-色满。该过程包括在通过氢芳基化或氢
乙烯基化步骤[Pd(OAc)2、Et3N、HCOOH、Bu4NCl、
甲苯]得到的粗混合物中加入t-BuONa、dppf以及适当的新鲜Pd(OAc)2。一般来说,4-芳基和4-
乙烯基-2,2-二烷基-3-色满可以高区域选择性获得,总产率从满意到高。
乙烯基三氟甲磺酸酯倾向于比芳基
碘提供更高的产率。