Table 3. Cycloisomerization of S3 Using Recycled C1 and C2^a.

entry	catalyst	NMR yield (%)
1	C1	90
2	C2	77
3b	C1	99
4b	C2	95
5c	C1	>99
6c	C2	>99

^aReaction conditions: 0.4 mmol of S3, 0.08 mmol of triethylamine, 0.012 mmol of Pd(II)-AmP-MCF, and 1 mL of toluene. The NMR yield was determined using 1,3,5-trimethoxybenzene as the internal standard.

^b1 mol % BQ used to reactivate the catalyst before the reaction.

^c1 mol % BQ added at the beginning of the reaction.