Lanthanide borohydrides as precursors to organometallic compounds. Mono(cyclooctatetraenyl) neodymium complexes

Reactions of Nd(BH4)(3)(THF)(3) (1) with KCp* (Cp* = eta -C5Me5), KC4Me4P, and K2C8H8 gave the organometallic derivatives (Cp*)Nd(BH4)(2)(THF)(2) (2), [K(THF)][(C4Me4P)(2)Na(BH4)(2)] (3), and (COT)Nd(BH4)(THF)(2) (4) (COT = eta -C8H8), respectively. Treatment of 4 with NEt3HBPh4 afforded the cationic complex [(COT)Nd(THF)(4)][BPh4] (5). The mixed ring compound (COT)Nd(Cp*)(THF) (6), the alkoxide [(COT)Nd(OEt)(THF)](2) (7), and the thiolates Na[(COT)Nd((SBu)-Bu-t)(2)] (8) and [Na(THF)(2)][{(COT)Nd}(2)((SBu)-Bu-t)(3)] (9) were synthesized by treating 4 or 5 with the alkali metal salt of the corresponding anionic reagent. The X-ray crystal structures of 7 and of a toluene solvate of 9 have been determined.