Reaction of Tris(2-thienyl)phosphine with Dirhodium(II) Acetate. Orthometalation of a Heteroaromatic π-System and an Unusual Ring Rearrangement

The reaction of tris (2-thienyl)phosphine (1)
with dirhodium(II) acetate in a 9:1 refluxing toluene/acetic acid mixture for 2 h leads to the formation of two
metalated compounds. The structure of one of them
contained two new orthometalated phosphines in a head-to-head arrangement, and, surprisingly, the metalated
thiophene rings, but not the nonmetalated ones, were
rearranged to a 3-thienyl structure. Both types of dirhodium compounds were assessed in a catalytic α-diazo ester
transformation.

将三(2-噻吩基)膦(tris(2-thienyl)phosphine，化合物1)与乙酸二铑(II)(dirhodium(II) acetate)置于体积比为9:1的回流甲苯/乙酸混合溶剂中反应2小时，可得到两种金属化产物。其中一种产物的结构中含有两个以头对头排列的新型邻位金属化膦配体；令人意外的是，仅金属化的噻吩环而非未金属化的噻吩环重排为3-噻吩基结构。随后对这两种二铑基金属化合物开展了α-重氮酯转化反应的催化性能评估。