Table 1.

Optimization of the reaction conditions.

Entry	Rh cat.	Solvent	Time (h)	Yielda	dr [syn:anti]b,c
1	RhCl(PPh3)3	THF	1	64	[3:1]
2	[RhCl(cod)]2	THF	1.5	72	[30:1]
3	RhClCO(PPh3)2	THF	1	85	[9:1]
4	Rh(acac)(CO)2	THF	1	trace	–
5	[RhCl(cod)]2	toluene	1	68	[14:1]
6	[RhCl(cod)]2	AcOEt	1	79	[25:1]
7	[RhCl(cod)]2	CH2Cl2	1	77	[31:1]
8	[RhCl(cod)]2	DME	2	17d	–
9	[RhCl(cod)]2	CH3CN	1	71	[2:1]
10	[RhCl(cod)]2	DMF	3	42	[1:27]
11	[RhCl(cod)]2	DMPU	1	52	[1:50]

^aIsolated yield; ^bthe stereochemistry between CH₃ (C^α) and OH (C^β) moieties; ^cdiastereomeric ratio was determined after purification; ^ddiastereomeric mixture.