Table 2.

Asymmetric alkylation of indole 5 with E-vinyldiazoacetate 1b

entry	catalyst	ratioa of 6/11/12	yieldb of 6 (%)	ee of 6 (%)
1	Rh2(OAc)4	62/33/5	57	---
2	Rh2(TFA)4	49/44/7	43	---
3	Rh2(esp)2	74/26/0	52	---
4	Rh2(S-PTAD)4	76/16/8	55	−8
5	Rh2(S-DOSP)4	26/38/36	22	17
6	Rh2(S-TISP)4	89/6/5	66	39
7	Rh2(S-biTISP)2	88/9/3	66	89

^aratio was the average of two runs and determined from the ¹H NMR of the crude reaction mixture.

^bisolated yield