Table 1.

Reaction Conditions: Carboxylate, Solvent, Temperature

entry	R	solvent	temp, time	yield (%)d
1	Oac	DMF	120 °C,b 24 h	69
2	Oac	CH3CN	120 °C,b 24 h	73
3	Oac	i-PrOH	120 °C,b 24 h	16e
4	OAc	t-amyl-OH	120 °C,b 24 h	33
5	OAc	EtOAc	120 °C,b 24 h	24e
6	OAc	toluene	120 °C,b 24 h	51e
7	OAc	DMA	120 °C,b 24 h	37
8	OPiv	DMF	120 °C,b 24 h	69
9	EH	DMF	120 °C,b 24 h	64
10	ND	DMF	120 °C,b 24 h	69
11	ND	toluene	120 °C,b 24 h	71
12	ND	DMF	120 °C,b 0.5 h	29e
13	ND	DMF	120 °C,c 0.5 h	27e
14	ND	DMF	160 °C,b 0.5 h	63
15	ND	DMF	160 °C,c 0.5 h	64

^aAll reactions were run with 3 equiv copper(II) carboxylate, 1 equiv Cs₂CO₃ at 0.1 M 1a concentration.

^bOil bath heating, pressure tube.

^cMicrowave heating.

^dAmount isolated after flash chromatography on SiO₂.

^eRemainder of the material is starting 1a. In entry 3 another cyclization product (net aminoetherification, incorporation of i-PrOH in the product) was also formed in 21% yield (see supplementary material). Ac = COCH₃, Piv = COC(CH₃)₃, neodecanoate (ND) = OCO(CH₂)₅C(CH₃)₃, ethylhexanoate (EH) = OCOCH(C₂H₅)C₄H₉