Table 1.

Precatalyst and Ligand Optimizations for the Cycloisomerization of 1

entrya	pre-catalyst	ligand	yield [%]b
			2	3
1	[Rh(=)2Cl]2	n-Bu3P	78	12
2	“	Ph3P	87c	8
3	“	Ph3P(20%)	70	2
4	“ (1 mol%)	Ph3P	71	3
5	“	(4-MeOC6H4)3P	43	4
6	“	(4-FC6H4)3P	61	1
7	“	t-Bu3P	22	5
8	“	Ph2MeP	81	9
9	[Rh(coe)2Cl]2	Ph3P	38	9
10	[Rh(cod)2Cl]2	Ph3P	57	20
11	RhCl(PPh3)3 (10 mol%)	-	24	49
12	[Rh(CO)2Cl]2	dppe	<1	83d
13	“	dppp	<1	29
14	“	dppb	<1	7
15e	“	dppe	<1	63
16	[Rh(=)2Cl]2	-	11	10

^aReactions used 5% of precatalyst and 10% of phosphine ligand at 0.05 M concentration of 1 in PhMe at 110 °C.

^bNMR yields based on internal standard.

^cIsolated yield: 77%.

^dIsolated yield: 77%.

^eConcentration: 0.1 M.