Compounds reaction with diborane

PES of, 16 78, 81 reaction with diborane, 16 276 trifluoroacetate, 17 9, 10 trihalides, 21 147-172, see also specific compounds adducts... 

Although catalytic hydrogenation in the presence of H2 and a catalyst such as Pt, Pd, Ni or Ru, reaction with diborane, and reduction by lithium, sodium or potassium in hydroxylic or amine solvents have all been reported to convert carbonyl compounds into alcohols, the most common reagents used for the reduction of carbonyl compounds are hydride donors. 

A number of oxygen and sulphur compounds are sufficiently powerful electron-pair donors to form borine adducts by reaction with diborane. Of these the unstable solid dimethyl ether borine, Me20+.BH3, used in the purification of diborane, is well known. 

Synthesis by high-dilution techniques requires slow admixture of reagents ( 8-24 hrs) or very large volumes of solvents 100 1/mmol). Fast reactions can also be carried out in suitable flow cells (J.L. Dye, 1973). High dilution conditions have been used in the dilactam formation from l,8-diamino-3,6-dioxaoctane and 3,6-dioxaoctanedioyl dichloride in benzene. The amide groups were reduced with lithium aluminum hydride, and a second cyclization with the same dichloride was then carried out. The new bicyclic compound was reduced with diborane. This ligand envelops metal ions completely and is therefore called a cryptand (B. Dietrich, 1969). 

Boron trifluoride is used for the preparation of boranes (see Boron compounds). Diborane is obtained from reaction with alkafl metal hydrides organoboranes are obtained with a suitable Grignard reagent. 

Methylarsine, trifluoromethylarsine, and bis(trifluoromethyl)arsine [371-74-4] C2HAsF, are gases at room temperature all other primary and secondary arsines are liquids or solids. These compounds are extremely sensitive to oxygen, and ia some cases are spontaneously inflammable ia air (45). They readily undergo addition reactions with alkenes (51), alkynes (52), aldehydes (qv) (53), ketones (qv) (54), isocyanates (55), and a2o compounds (56). They also react with diborane (43) and a variety of other Lewis acids. Alkyl haUdes react with primary and secondary arsiaes to yield quaternary arsenic compounds (57). 

An important stage in the synthesis has been reached. The reaction processes described thus far have proceeded uneventfully and have culminated in the synthesis of compound 9. The stage is now set for an evaluation of the first of two hydroboration reactions. Treatment of 9 with diborane in THF, followed by standard alkaline hydrogen peroxide workup, furnishes an 8 1 stereoisomeric mixture of alcohols in favor of 28 (85 % total yield). On the basis of some important precedent,32 it is presumed that compound 9 preferen-... 

My thesis was completed in 1938 and the results were published in 1939 Hydrides of Boron. XI. The Reaction of Diborane with Organic Compounds Containing a Carbonyl Group (3). 

Reaction of the salts of primary and secondary alky Initio compounds with diborane in THF solution at 25 °C yields the corresponding hydroxylamines.117 Kabalka has reported the reduction of nitroalkenes to hydroxylamines or amines with a variety of borane and borohydride reagents (Eq. 6.61).118... 

Borazine originally was obtained by the reaction of ammonia with diborane.1 Mixtures of lithium or sodium tetrahydro-borate with ammonium chloride also have been pyrolyzed to yield this product.2 More recently, the reduction of B,B, B"-trichloroborazine with alkali metal hydroborates has proved to be a convenient laboratory-scale method for the preparation of this compound.3-7 The procedure described herein is a variation of the last method as reported by Dahl and Schaeffer.7 This method is effective for the synthesis of iV-substituted alkyl- and arylborazines, i.e., compounds of the formula (HBNR)3 where R is CH3, C2H6, C6H , C6H5, p-C6H4CH3, or p-C6H4OCH3.5... 

The compound C13CH=NBH2 is obtained upon reaction of trichloroaceton-itrile with diborane during the synthesis of 1,3,5-trichloroethylborazine (Eq. (13) 16)) it is undoubtedly not monomeric as indicated by its i.r. spectrum (v BH2 cm-1, v C=N 1705 cm-1 22>) Most likely the material is dimeric and it is difficult to isolate in pure form due to the ready conversion to the bor-azine derivative. 

Alternatively, the compound may be obtained by the reaction of ethyllithi-um with diborane ... 

Problem 15.64 Isopropyl chloride is treated with triphenylphosphine (Ph P) and then with NaOEt. CH3CHO is added to the reaction product to give a compound, C,H, . When C5H, is treated with diborane and then CrO, a ketone is obtained. Give the structural formula for C,H, and the name of the ketone. d... 

The greater part of the modification studies of silica with boron compounds has been directed towards achieving an understanding of the surface structure of silica and silica based adsorbents, utilizing the quantitative reactions with boron containing probe molecules. Because hydroxyl type specificity occurred in some reactions, boron compounds were used to make a distinction between isolated and vicinal surface hydroxyls. Diborane was even utilized as a probe to distinguish surface silanols from hydration water.6,7... 

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