Table 1.

Optimization of the Fluoride Source and Solvent for the Macrocyclization^a

entry	fluoride source	equiv	solvent	yield, % 8a+8a'	ratiob8a+8a'
1	TBAF•3H2O	10	THF	0	-
2	TBAF•3H2O	10	THF	43	3:1
3	TBAF•4H2O	10	THF	64	3:1
4	TBAF•6H2O	10	THF	59	3:1
5	TBAF•6H2O	5	THF	72	3:1
6	TBAF•6H2O	2.5	THF	26	3:1
7	TBAF•6H2O	5	dioxane	76	3:1
8	TBAF•6H2O	5	DMF	84	2:1
9	TBAF•7H2O	5	DMF	79	2:1
10	TBAF•10H2O	5	THF	46	100:0
11	TBAF•15H2O	5	THF	39	100:0

^aReaction conditions employed 0.25 mmol of 7a at 0.1 M.

^bRatio determined by ¹H NMR analysis.