ISSN:
0009-2940
Keywords:
(Iminoboryl)borates
;
(Aminoboryl)boranes
;
Trialkyl(amino)diboranes(4)
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
(Iminoboryl)borates [R3B—B=NR]-: Rearrangement to (Aminoboryl)boranes R2B—BR=NRE by the Addition of Electrophiles E(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, MeI, Me3SiI) are obtained, when the polar compounds EX are added to 2a, accompanied 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 [R′3B-C≡R″] to R′2B-CR′=CR″E.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19961290318
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