Table 1.

Reaction Optimization and Control Reactions.^a

entry	Y	change in conditions	yield 3 (%)b	yield 4 (%)
1	Cl	None	89	3
2	Cl	No dtbpy	8	7
3	Cl	terpyridine in place of dtbpy	27c	<1
4	Cl	1 equiv 1 instead of 1.5 equiv	69	3
5	Cl	1.5 equiv 2, 1 equiv 1	56	2
6	Cl	No nickel	6d	5
7	Cl	No nickel, no dtbpy	8d	4
8	Cl	No Mn	0d	25
9	Cl	Zn in place of Mn	41	1
10	Spy	None	37	43
11	Spy	Zn in place of Mn	53	25
12	Spy	Pre-stir catalyst with Zn for 1 h	71	10
13	Spy	As in Entry 12, but 1 equiv 1	71	6

^adtbpy = 4,4′-di-tert-butyl-2,2′-bipyridine. Terpyridine = 4,4′,4″-tri-tert-butyl-2,2′:6′,2″-terpyridine. Reactions were run on 0.5 mmol scale in 2 mL of N,N-dimethylacetamide (DMA). See Supporting Information for details.

^bYield determined by GC analysis, uncorrected.

^cAlkyl dimer was the primary side-product (54% with respect to iodooctane). Alkyl dimer was not a significant byproduct in Entry 1.

^d>50% of R-I starting material remained.