176683-30-0Relevant academic research and scientific papers
(Iminoboryl)borates [R3B-B=NR]-: Rearrangement to (aminoboryl)boranes R2B-BR=NRE by the addition of electrophiles E
Luckert, Stefan,Englert, Ulli,Paetzold, Peter
, p. 361 - 365 (1996)
(Iminoboryl)borates [Li(tmeda)2][R2R′B-B≡NR] (2a-c, R′ = Me, Me3SiCH2, Me3CCH2) are formed from the azadiboriridine NB2R3 (1, R = tBu) and LiR′ in the presence of tmeda. Vinyllithium brings about a ring expansion of 1 to give the five-membered anionic ring [-CH=CH-BR=NR-BHR-]-, to which [Li(tmeda)]+ is bound (3). The (aminoboryl)boranes R2B-BMe=NER (4a-c, EX = HCl, Mel, Me3SiI) are obtained, when the polar compounds EX are added to 2a, accom-panied by the elimination of LiX and the migration of Me. The borate 2b reacts with HCl to give a mixture of the isomers R2B-B(CH2SiMe3)=NHR (4d) and R(Me3SiCH2)-B-BR=NHR (4d′), and 2c reacts with HCl to yield the borane R(Me3CCH2)B-BR=NHR (4e′) exclusively. The transformation of [R2R′B-B≡NR]- to R2B-BR′ =NRE by the attack of electrophiles E corresponds to the known transformation of [R3′B-C≡CR″]- to R2′B-CR′ = CR″E. VCH Verlagsgesellschaft mbH, 1996.
