Benzyl tri-n-butylammonium chloride

Benzyl a-toluate. See Benzyl phenylacetate Benzyl tributyl ammonium chloride CAS 23616-79-7 EINECS/ELINCS 245-787-3 Synonyms Benzyl tri-n-butylammonium chloride BTBAC Classification Quaternary Empirical C19H34CIN... 

Benzyl tri-n-butylammonium chloride. See Benzyl tributyl ammonium chloride Benzyl trichloride. See Benzotrichloride Benzyltriethyl ammonium bromide CAS 5197-95-5 Empirical CisH22BrN Properties M.w. 272.23 m.p. 194 C Storage Hygroscopic... 

Typical procedure. 1,2,2,2-Tetrachloroethyl chloroformate 103 [58] Freshly distilled chloral (4.4 g, 0.030 mol) was added (over 30 min) to a stirred refluxing solution (dry-ice Dewar condenser) of benzyl tri-n-butylammonium chloride (BTBAC) (10 g, 0.032 mol) in phosgene (for a safe source, see Chapter 7) (60 mL). After 1 h, the excess phosgene was removed through a series of five bubble traps (empty, H2SO4, empty, aqueous NaOH, NH4OH to hood exhaust) with the aid of an aspirator, and the 1,2,2,2-tetrachloroethyl chloroformate was isolated by distillation bp 76-79 °C/19 Torr, 47.7 g (65% yield). Note Unless 1,2,2,2-tetrachloroethyl chloroformate is completely free from the catalyst, it slowly reverts to the reactants. 

The large-scale synthesis of a-chloroethyl chloroformate (ACE-Q) by the above method (stirring acetaldehyde with 1.1 equiv. of neat pho ene for 1 h in the presence of 3.0% benzyl tri-n-butylammonium chloride (BTBAC), giving an isolated yield of 96%) has a particular value since its ethanolysis product, a-chloroethyl ethyl carbonate, is a commercial alkylating agent used to mask carboxyls in penicillins and cephalosporins. 

Ion-pair extraction. Iodides are extracted into methylene chloride or similar solvents much more readily than the corresponding chlorides. This ion-exchange method is used to convert trimethyloxosulfonium iodide into the chloride. Thus on distribution of this iodide and an equimolecular amount of the quaternary chloride between methylene chloride and water, the organic phase contains benzyl tri-n-butylammonium iodide and the water phase contains trimethyloxosulfonium chloride. The ion exchange is practically complete. Note that trimethyloxosulfonium chloride is preferred to the iodide for generation of dimethyloxosulfonium methylide because the chloride is more soluble in THF (1,315). ... 

Benzyl chloride added dropwise during 2 hrs. at pH 7.5-8 to a soln. of chloro-(glycinato)(tri-n-butylphosphine)platinum(II), NaOH, and tetra-n-butylammonium hydrogen sulfate in acetone containing a little water, and stirred 3 hrs. at room temp. -> chloro(phenylalaninato)(tri-n-butylphosphine)platinum(II). Y 70-80%. - This is part of a method for the synthesis of a-aminocarhoxylic acids. F. e. with dimethyl sulfate and aldehydes s. W. Beck and M. Girnth, B. 109, 965 (1976). 

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