69737-51-5

Upstream product

• 108-86-1 bromobenzene 
• 5419-55-6 Triisopropyl borate 
• 591-51-5 phenyllithium 
• 100-58-3 phenylmagnesium bromide 
• 1692-26-8 bis(propan-2-yl) phenylboronate 
• 4406-77-3 2-Phenyl-1,3,2-dioxaborinane 

Downstream Products

• 2622-89-1 diphenylborinic acid 

Relevant academic research and scientific papers

Tuning of the colour and chemical stability of model boranils: A strong effect of structural modifications

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.

Palladium-catalyzed cross-coupling reaction of potassium diaryldifluoroborates with aryl halides

The catalytic cross-coupling reaction of potassium diaryldifluoroborates with aryl halides proceeds to afford the biphenyls in good yields. These salts on an arylation reagent were readily prepared via a protocol of the Grignard method and transformation to potassium salts. Two aryl groups of these salts were efficiently transferred in the Suzuki-Miyaura reaction.

Selective preparation of borinic esters from Grignard reagents and selected trialkoxyboranes

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.

Process for lithium mono- and diorganylborohydrides

Improved processes for liberating boronic, RB(OR')2, and borinic, RR'BOR', esters from their "ate" complexes, free of alcohol are provided. Pyrolysis of lithium organylborates LiRB(OR')3 and LiRR'BOR', wherein R is an organyl group and R' is straight or branched-chain lower alkyl, directly yields the relatively volatile boronic and borinic esters in high purity, leaving behind a residue of lithium alkoxide. Treatment of the lithium organylborates with an appropriate acid halide cleanly liberates either volatile or non-volatile boronic or borinic esters, readily separated from the lower alkyl ester produced as a by-product. The novel compound lithium dimethylborohydride is also provided.

Organoboranes. 48. Improved procedures for the preparation of boronic and borinic esters

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.

Organoboranes. 40. A simple preparation of borinic esters from organolithium reagents and selected boronic esters

Monoorganyldiisopropoxyboranes, RB(O-i-Pr)2, react cleanly at -78 °C with 1 equiv of organolithium compounds, R′Li, to form the corresponding complexes of the borinic acid esters, LiRR′B(O-i-Pr)2. Treatment of these complexes with an equivalent of anhydrous hydrogen chloride in ethyl ether liberates the borinic esters, RR′BO-i-Pr, and isopropyl alcohol, usually readily separated by distillation. Alternatively, treatment of the complexes with 1 mol of an appropriate acid chloride liberates the borinic esters, RR′BO-i-Pr, and an isopropyl ester, RCO2-i-Pr. By careful selection of the acid chloride, these two products can be easily separated by distillation. A careful examination of the reaction of other boronic esters in this reaction revealed that the boronic esters of 1,3-propanediol forms the 1:1 complex cleanly on reaction with organolithium compounds at -78 °C. (Formula Presented) Treatment of these ate complexes either with hydrogen chloride in ether or with an appropriate acid chloride provides the pure borinic ester. Consequently, simple rational procedures are now available for the synthesis in high purities and yields of either boronic or borinic acids and esters, either through hydroboration or through the use of organolithium compounds.

Organoboranes. 31. A simple preparation of boronic esters from organolithium reagents and selected trialkoxyboranes

The reaction of methyllithium with trimethoxyborane at -78°C in ethyl ether yields a mixture of methylated boranes and their corresponding ate complexes. We have found that under the same conditions triisopropoxyborane reacts cleanly with methyllithium to form the lithium methyltriisopropoxyborate complex. Protonation of this complex with anhydrous hydrogen chloride quantitatively yields methyl diisopropoxyborane. This reaction of organolithium reagent with triisopropoxyborane appears to provide a general, valuable route to boronic esters. Other alkoxyboranes were examined for their selectivity for monomethylation by methyllithium. In addition to triisopropoxyborane, triisobutoxyborane and tri-sec-butoxyborane also give the methylboronic esters quantitatively. This development provides the first general preparation of boronic esters from organolithium reagents.