CONTRIBUTIONS TO THE CHEMISTRY OF BORON .214. SYNTHESIS AND REACTION CHEMISTRY OF AMINOPHOSPHANYLBORANES

Aminochlorophosphanylboranes, (R2N)B(Cl)P(SiMe3)2 (1a-d) and (R2N)B(Cl)PH2 (2a-d), are obtained from elimination reactions between aminochloroboranes and LiP(SiMe3)2 and LiPH2, respectively. Selected reaction chemistry of (i-Pr2N) B(Cl)[P(SiMe3)2] (1a) with NH3, Me3SiN3, Cr(CO)5.NMe3, and W(CO)5 . NMe3 is described. The azide (i-Pr2N)B(N3)P(SiMe3)2 (12a) is stable at 25-degrees-C; however, thermolysis at 80-degrees-C provides a novel six-membered ring compound [(i-Pr2N)BN(SiMe3)P(SiMe3)]2 (13a). The reaction of (Ph2N)B(CI)P(SiMe3)2 (1b) with LiP(SiMe3)2 produces the only isolable bis(phosphanyl)borane (5b), while combination of (R2N)B(CI)PH2 with LiPH2.DME yields new diphosphadiboretanes 6 {(R2N)BPH}2 (R2N = i-Pr2N, Ph2N and tmp = 2,2,6,6-tetramethylpiperidino) and triphosphatriborinanes 7 {(R2N)BPH}3 (R2N = (Me3Si)2N, Me2N and Et2N). Two salts, [(i-Pr2N)BP(H)B(i-Pr2N)PLi . DME]2 (8a) and [tmpBP(H)-B(tmp)PLi . DME]2 (8C) (DME = ethylene glycol dimethyl ether) are also isolated. The results of molecular structure determinations for [(i-Pr2N)Bn(SiMe3)P(SiMe3)]2 (13a), [tmpBPH]2 (4c), [tmpBPH]2.Cr(CO)5 (7c), {[(Me3Si)2N]BPH}3 (4d), {[(Me3Si)2N]BPH}3 . Cr(CO)5 (7d), (Ph2N)B[P(SiMe3)2]2 (5b), and [(i-Pr2N)BP(H)B(i-Pr2N)PLi . DME]2 (8a) are discussed.