The novel M[(OPPh2)(2)N](2)center dot nTHF (M = Sr (2), Ba (3)) complexes were prepared and characterized. Upon exposure to atmospheric oxygen, 2 and 3 were transformed to the dinuclear species Sr-2-[(OPPh2)(2)N](4)center dot 2C(3)H(6)O(3) (4) and Ba-2[(OPPh2)(2)N](4)center dot 2C(4)H(8)O(3) (5), respectively. Compounds 4 and 5 contain coordinated carboxylic acids obtained from the oxidative degradation of DME and THF, respectively, which were used as solvents for crystallization.