Optimization of ring-closing metathesis reaction conditions.

Entry	Catalyst	Catalyst loading (mol%)	Reaction cyclesa	Substrate conc. (mM)	Time	Yieldb (%)
1	Grubbs 1st gen	10	1	6	2 h	90
2	Grubbs 2nd gen	10	1	6	1 h	91
3	Zhan-1b	10	1	6	1 h	93
4	Grubbs 2nd gen	5	1	6	1 h	91
5	Grubbs 2nd gen	2	1	6	1 h	96
6	Hoveyda–Grubbs 2nd gen	2	1	6	1 h	95
7	Zhan-1b	2	1	6	1 h	96
8	Zhan-1b	1	1	6	1 h	95
9	Zhan-1b	1	2	5	2 × 1 h	94
10	Zhan-1b	1	5	5	5 × 1 h	96

^aRepeat cycles of substrate and catalyst addition in same vessel.

^bIsolated yield.