A catalytic asymmetric nitroso aldol intramolecular transesterification cyclization domino reaction between a C3 alkyl ester substituted oxindole and nitrosobenzene for the construction of chiral spirooxindoles was achieved in the presence of a chiral bifunctional tertiary amine thiourea catalyst and water. Optically active spirooxindoles were obtained in moderate yields (up to 76 %) and excellent enantioselectivities (up to 95 % ee).

An improved, concise, and efficient preparation of the telaprevir bicyclic [3.3.0] proline intermediate is presented. The key steps, control points, and the whole process are optimized. The synthesis of racemic intermediate was accomplished in five steps in above 56% overall yield up to 100 g scale with only some simple separations and treatments in the whole process. The new and crucial chiral resolution of the proline intermediate was systematically studied, and the target chiral intermediate was obtained in acceptable yield (30%) and excellent ee value (>99% ee) by a simple washing. The cost of the target chiral intermediate and wastes of the whole process were at least doubly reduced after the effective reuse of the unwanted chiral amino acid by successful decarboxylation.