在催化量的三苯甲基盐(例如 TrOTf、TrSbCl6、TrPF6、TrSnCl5 等)存在下,甲硅烷基烯醇醚与醛反应以良好的收率得到相应的羟醛。The preferential formations of erythro or threo aldols become possible by the suitable choice of the counter anions of these trityl salts and the substituents on silicon of the enolates.