Table 2.

entry	internal alkyne	terminal alkyne	yield a	rrb	major regioisomer
1		36	60	17:1
2		36	57	≥ 20:1
3		36	47	≥ 20:1
4		36	53	≥ 20:1
5		ent-36	64	≥ 20:1
6		ent-36	63	≥ 20:1
7		ent-36	64	≥ 20:1
8		ent-36	68	≥ 20:1
9		36	78	10:1

^aYield based on terminal alkyne

^bRegioisomeric ratio with respect to functionalization of the internal alkyne (A/B – defined in Table 1). In a few cases, observable quantities of the minor regioisomer “C” were observed (entry 4 = 12:1, entry 6 = 14:1, entry 7 = 17:1).