Boron diamide derivatives containing N–N and N–P molecular fragments

Abstract

The cationic and neutral boron–diamide precursors are employed to target the inclusion of N₂ and N–P molecular fragments. The species (HCN(Dipp))₂BNH₂5, and (H₂CN(Dipp))₂BNH₂6 were prepared. While efforts to oxidize with [NO]⁺ gave mixtures of products, reactions with N₂H₄ gave the salts [(HCN(Dipp))₂B(NHNH₃)][O₃SCF₃] 7 [(H₂CN(Dipp))₂B(NHNH₃)][O₃SCF₃] 8. Excess N₂H₄ gave the neutral species (HCN(Dipp))₂B(NHNH₂) 9 and (H₂CN(Dipp))₂B(NHNH₂) 10, respectively. The species (H₂CN(Dipp))₂B(N₃) 11 was prepared for comparative purposes. Turning to related NP species, compound 6 was converted to (HCN(Dipp))₂B(NHPCl₂) 12, while (HCN(Dipp))₂BNK(SiMe₃) 14 was used to give (HCN(Dipp))₂BN(SiMe₃)PCl₂15. Replacement of one of the chlorides gave (HCN(Dipp))₂BN(SiMe₃)PCl(OSO₂CF₃) 16 which converts to [(HCN(Dipp))₂BNPCl]₂17. Similarly heating 15 afforded 17. The insights for the synthesis of further boron-N₂ and boron-NP derivatives are discussed.