Phenylboron dichloride

The first authenticated borole (94) was made by the exchange reaction of phenylboron dichloride with l,l-dimethyl-2,3,4,5-tetraphenylstannole (93) (Eq. 29)w in toluene. 

Sundar and Keller have reported the synthesis of linear boron-silicon-diacetylene polymers (31) (Fig. 21) using phenylboron dichloride (PBD) as the source for boron.50 The compositions of the thermally stable boron-silicon-diacetylene copolymers 31a-d are summarized in Figure 21. These polymers were observed to possess exceptional thermooxidative stabilities. 

Phenyl benzoate Phenylboron dichloride Phenylcyclopropane iV-Phenyldiacetimide Phenyl formate Phenylhydrazine 16.43... 

The present procedure is also applicable to the synthesis of substituted benzeneboronic acids.4 Benzeneboronic acid and its anhydride are of use as starting materials for the synthesis of phenylboron dichloride 12 and of various substituted boronic and borinic acids and esters.6 13... 

Bao and Wulff compared catalysts prepared from vaulted biaryls and from bromo-borane dimethylsulfide with those generated from linear biaryls with regard to their capacity to provide enantioselective induction in the Diels-Alder reaction of cyclo-pentadiene and methacrolein (Eqs 6 and 7) [7]. Because the (5) enantiomers of vaulted biaryls result in induction opposite to that resulting from use of the (5) enantiomer of binaphthol, and because effective catalysts cannot be generated from binaphthol and phenylboron dichloride, suggest that the catalysts obtained from vaulted biaryls do not have the same structure as the Cs-symmetrical catalyst produced from binaphthol. 

Dihydro-l,2-oxastannole 204 undergoes a similar exchange with phenylboron dichloride to afford 2,5-dihydro-1,2-oxaborole 205 <20040M5088>. This synthesis is particularly convenient since the tin compound can be easily prepared by the hydrostannation of propargyl alcohol (Scheme 28) <1973SRI1>. 

The new boron-aromatic tricyclic compound (380) and some isomeric systems were obtained in good yield through reaction of the appropriate ortho-aminobithienyl with phenylboron dichloride. Proton... 

Catalyst lOd was prepared sinply by treatment of iV-(/ -toluenesuIfonyl)-(5)-tryptophan with 3,5-bis(trifluoromethyl)phenylboron dichloride and subsequent removal of the produced HCl in vacuo (eq 15) (26). The 5-Aryloxazaborolidine could not be prepared from the arylboronic acid. 

A soln. of benzoin in methylene chloride added with stirring under dry Ng during 1.5 hrs. to a soln. of phenylboron dichloride in the same solvent, and refluxed 1 hr. 2,4,5-triphenyl-l,3,2-dioxaborole. Y 58%. F. e. s. K. A. Jensen and T. Pedersen, Acta Ghem. Scand. 15, 1780 (1961). 

C6H5BCI2, Phenylboron dichloride (gas-ed), 15, 417 19, 545 C6H5BF2, Phenylboron difluoride (gas-mw), 40B, 1145 CgHgBBrOz, 4-Bromophenyl boric acid, 22, 691... 

Propane-1,3-dithiol added dropwise with vigorous stirring at room temp, under Ng to phenylboron dichloride in dichloromethane until the pink color of the soln. disappears, solvent and HCl removed in vacuo and the residue distilled at 0.1 mm 2-phenyl-1,3,2-dithioborinan. Y 90%. F. e. s. A. Finch and J. Pearn,... 

When the reduction of phenylboron dichloride is carried out with lithium aluminum hydride at the reflux temperature of dioxane (100 C) only the disproportionated products, triphenylborane and diborane, are found (7J). In contrast, a similar reduction of diethylphenylboronate in diethyl ether at room temperature gives the phenylborane (dimer) which is isolated as the pyridine adduct (74). Also, l-butoxy-3-methylboracyclopentane (VI) is reduced without difficulty by lithium aluminum hydride in ether solution to the corresponding tetrasubstituted diborane (VII) (75). 

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