69737-51-5Relevant articles and documents
Tuning of the colour and chemical stability of model boranils: A strong effect of structural modifications
Wesela-Bauman, Grzegorz,Urban, Mateusz,Luliński, Sergiusz,Serwatowski, Janusz,Wo?niak, Krzysztof
supporting information, p. 3268 - 3279 (2015/03/18)
A series of diarylborinic complexes with salicydeneaniline ligands bearing various functional groups at the 6-position have been synthesized in high yields by applying a straightforward one-pot multicomponent protocol. UV-Vis measurements revealed the influence of electronic character of substituents on the observed maximum of emission (λem). This has been confirmed by a relatively strong linear correlation (R2 = 0.92) of λem with Hammett σp+ constants. Such a correlation was investigated using a QTAIM analysis of the charge density distribution. Absorption and emission bands for the obtained systems span between 390-437 nm and between 506-590 nm, respectively, with quantum yields reaching 17%. Time-dependent UV-Vis absorption measurements revealed that diphenylborinic salicydeneaniline complexes undergo slow degradation in solution under ambient conditions. In contrast, the use of a naphthalene-based chromophore or the introduction of fluorinated phenyl groups at the boron atom resulted in stable systems.
Selective preparation of borinic esters from Grignard reagents and selected trialkoxyboranes
Cole, Thomas E.,Haly, Becky D.
, p. 652 - 657 (2008/10/08)
The reaction of trialkoxyboranes with ethylmagnesium bromide was investigated for the selective alkylation to the symmetrical borinic esters, R2BOR′. Triisopropoxyborane was found to react cleanly with 2 equiv of the Grignard reagent to form diethylisopropoxyborane at -40°C. The selectivity of this reaction is largely controlled by the stability of the bromomagnesium diethyldiisopropoxyborate, MgBr[Et2B(OiPr)2]. Triisopropoxyborane was found to be the most selective borane examined, yielding symmetrical borinic esters for primary and aryl derivatives with high selectivities. Secondary alkyl groups showed lower selectivities. This reaction has been developed into a general procedure for preparation of diorganylalkoxyboranes from readily available organomagnesium reagents, especially for those containing organic groups which are not accessible via hydroboration.
Organoboranes. 48. Improved procedures for the preparation of boronic and borinic esters
Brown, Herbert C.,Srebnik, Morris,Cole, Thomas E.
, p. 2300 - 2303 (2008/10/08)
Two improved procedures for liberating boronic, RB(O-i-Pr)2, and borinic, RR′BO-i-Pr, esters from their ate complexes, free of isopropyl alcohol, have been developed. Pyrolysis of lithium organylborates, LiRB(O-i-Pr)3 and LiRR′B(O-i-Pr), directly yields the relatively volatile boronic and borinic esters in high purity, leaving behind a residue of lithium isopropoxide. Treatment of the lithium organylborates with appropriate acid chlorides, usually acetyl or benzoyl, cleanly liberates either volatile or nonvolatile boronic or borinic esters, readily separated from the isopropyl ester produced as a byproduct. These developments greatly facilitate the preparation of boronic and borinic esters in high purity.
