First Structurally Authenticated Heavier Alkali Metal Phosphinomethanide

Metathesis between Li[C(SiMe3)2{P(C6H4-2-CH2NMe2)2}] (1) and KO-t-Bu yields [{K[C(SiMe3)2{P(C6H4-2-CH2NMe2)2}]}2] (2), the first heavier alkali metal complex of a phosphorus-stabilized carbanion to be structurally characterized.