Development of Environmentally Benign Selective Organic Reactions with Allylpolyindium Reagents

以金属铟和3-溴-1-碘丙烯为原料，在Pd(0)催化剂的作用下，依次与羰基化合物、芳基卤化物、烯基卤化物或烯基卤化物偶联，合成了一种新型烯丙基二铟试剂，方便了线性烯丙基醇的一锅合成。因此，开发了一种基于烯丙基双铟试剂的新型级联剂。由3-溴-1-碘丙烯和4-溴-2-碘-2-烯制备的二铟试剂，先与亚胺反应，然后在Pd(PPh_3)_4存在下用有机卤化物处理得到线性n -芳基和N-tosyl同烯丙基胺。从3-溴-1-碘丙烯中得到的铟在溶剂中少量的水中是稳定的，而从4-溴-2-碘-2-烯中得到的铟很容易质子化，得到一个丁基铟试剂。后一种二铟与苯甲醛的反应主要是通过与两个醛分子的自发偶联得到1,3 -和1,5 -二醇，而前一种反应是与一个羰基化合物分子反应得到乙烯基化合物。

A novel allylic diindium reagents were synthesized by the reaction of indium metal with 3-bromo-1-iodopropene, which successively coupled with carbonyl compounds and then with aryl, alkenyl or allyl halides in the presence of a Pd(0) catalyst to afford a convenient one-pot synthesis of linear homoallylic alcohols. Thus, a new cascade based on the allylic diindium reagent has been developed.The di indium reagents, prepared from 3-bromo-1-iodopropene and 4-bromo-2-iodobut- 2-ene, were initially reacted with imines and the resulting vinylindium compounds were then treated with organic halides in the presence of Pd(PPh_3)_4 to give linear N-aryl and N-tosyl homoallylic amines. The diindium from 3-bromo-1-iodopropene is stable in a small amount of water in solvent, whereas the di indium from 4-bromo-2-iodobut-2-ene is easily protonated to give a crotylindium reagent. The reaction of the latter di indium with benzaldehyde gives mainly the 1, 3- and 1, 5-diols via a spontaneous coupling with two molecules of the aldehyde, in contrast to the former which reacts with one molecule of carbonyl compounds to give the vinylindium compounds.