CYCLOHEXADIENYL URANIUM COMPLEXES

The potassium salt of the 6,6-dimethylcyclohexadienyl anion, (dmch)K, reacted with U(BH4)4 (I) to give (dmch)2U(BH4)2 (II), whereas (dmch)U(BH4)3 (III) was obtained from an equimolecular mixture of II and I. The anionic compounds [(dmch)2UX2][K(18-crown-6)] (X = Cl, IV; BH4, V) were synthesized by treatment of UCl4 or (mesitylene)U(BH4)3 with (dmch)K. The neutral complex (dmch)2U-(BH4)(THF) (VI) was isolated by extracting the powder of [(dmch)2U(BH4)2][K(THF)x] with pentane; VI reacted with OPPh3 to give (dmch)2U(BH4)(OPPh3) (VIII). © 1990.