Substrates with multiple stereocenters

This work presents the first catalytic enantioselective cyclization strategy for accessing steroidal and terpenoidal frameworks using organocatalysis. It should be pointed out that the present domino cycHzation could be conducted at room temperature. The asymmetric construction of multiple C-C bonds and contiguous stereocenters using substrate 263 in the presence of the chiral imidazolidinone 259 resulted in the formation of 264 with four new C-C bonds, seven stereogenic centers, and three quaternary carbon centers with about 90% yield for each chemical bond formation and over 90% ee. 

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