Stannic acetate trichloride

Lemieux and Brice33 have studied the rearrangement under the conditions employed by Pacsu,80 involving the use of stannic chloride as catalyst, with pure chloroform as solvent. The reaction was shown to be specific for the anomeric center, and the following observations appear to establish definitely the main features of the mechanism for this reaction. A quantitative yield of silver chloride was obtained on treating silver acetate with an excess of stannic chloride in chloroform, and it seemed probable that there results a chloroform solution of stannic chloride and stannic trichloride acetate (LVIII). The solution was able to catalyze the anomerization. 

It was reasoned that if the anomerization were carried out in the presence of C14-labeled stannic trichloride acetate (LVIII), and if exchange between this substance and the ion (LIX) were sufficiently rapid (equation 5), the resulting... 

The D-mannopyranose pentaacetates were treated with stannic trichloride acetate (labeled with carbon14 in the carboxyl group) in chloroform solution, in the presence of stannic chloride. The rate at which radioactivity was introduced into the sugar acetate was followed. The exchange had been shown to be specific for the Cl-acetoxy group of the D-glucopyranose pentaacetates,33 and this was assumed in the present... 

Red phosphorus is less soluble than white in all solvents. In water and alcohol it is almost insoluble. It is somewhat soluble in ether and in hot acetic acid, from which it is reprecipitated by water. It is slightly soluble in phosphorus trichloride. These solubilities refer to the ordinary preparation, which, as shown on p. 32, usually contains residual quantities of the white form. Red phosphorus is able to reduce salts, especially those of the noble metals, in aqueous solution on boiling. Salts of mercury are reduced to the metal those of gold and silver give insoluble phosphides while ferric and stannic salts are reduced to ferrous and stannous respectively.5... 

Lemieux and Brice have measured the rate of exchange (in chloroform) of a large number of 1,2-trans sugar acetates with stannic trichloride acetate labeled with C. Their results are given in Table XVII. The low reactivities of the acetates of 8-D-ribose, a-D-lyxose, 8-D-allose, and a-D-mannose (rela-... 

Relative Rates of Exchange of Acetate Between 1, -trans Sugar Acetates and Stannic Trichloride Acetate ... 

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