Table 2.

New Palladium Species Formed by Exposure of [COP-OAc]₂ (4) to Carboxylic Acids^a

entry	R	4:new COP speciesb	SN2′ reactivity of RCO2Hc	pKa
1	adamantyl	1:3.6	26	6.8
2	t-Bu	1:7.8	40	5.0
3	p-MeC6H5	1:4.6	67	4.4
4	Ph	1:10.8	84	4.2
5	o-ClC6H4CH2	1:3.1	92	4.1
6	ClCH2CH2	1.2:1	40	4.0
7	MeOCH2	1:5.0	38	3.6
8	Cl2CH	0:>95	14	1.3

^a[4] = 9.3 mM, [RCO₂H] = 18.6 mM, CD₂Cl₂.

^bMeasured as the sum of all dimeric or heterodimeric species that are not homodimeric 4. See Supplementary Information for more details.

^c% Conversion after 24 h: [imidate 1 (R = Bn)] = 0.5 M, 3 equiv RCO₂H, 1 mol % 4, in CD₂Cl₂, 23 °C.