BENZYL PHOSPHINES AND THEIR DERIVATIVES. 611 



Zinc Benzyl Phosphinite. — Obtained by adding acetate of zinc in excess to a rather 

 dilute solution of the acid and boiling for some time, when the compound was deposited 

 as a granular crystalline powder. The salt is anhydrous. 



Analysis. 



(i.) 03044 gave 0-067 ZnO = 00537 Zn = 17 -64 per cent. 



(ii.) 05145 „ 01133 „ =009091 „ =17-66 



(m.) 0-8757 „ 01946 „ =0-15616 „ =1783 



Obtained. 



< * < Calculated for 



I. II. III. {(C 7 H 7 )HP0 2 } 2 Zn 



Zinc, . . 17-64 1766 1783 17-33 



Cadmium Benzyl Phosphinite. — This salt was prepared by decomposing a solution 

 of the barium salt with the equivalent quantity of cadmium sulphate, filtering from the 

 sulphate of barium and evaporating the filtrate. When the solution grew concentrated 

 a white flocculent salt separated, which was filtered off and analysed. The mother-liquors, 

 when further concentrated, gave a slimy deposit, and on cooling a crystalline salt. 



Analysis. 



0-4953 gave 01569 CdO = 0137287 Cd = 2771 per cent. 



Obtained. Calculated for {(C 7 H 7 )HP0 2 } 2 Cd 



Cadmium, . . . 27-71 26-54 



Lead Benzyl Phosphinite. — A rather concentrated solution of the pure phosphinous 

 acid (obtained by decomposing the barium salt with sulphuric acid) was mixed with the 

 calculated quantity of acetate of lead. The solution was filtered from a slight white 

 precipitate which had been thrown down, slightly acidulated with acetic acid and warmed, 

 when a colourless crystalline salt was precipitated. It was rapidly washed, dried, and 

 analysed. 



Analysis. 



0-4269 (air-dried salt) lost at 110° C. 0-0061 H 2 0= 1-42 per cent. 

 04269 gave 0-2446 PbS0 4 = 01671 Pb =3914 „ 



Obtained. Calculated for 2(C r H 7 HP0 2 ) 2 Pb,H 2 



Water, .... 1-42 114 



Lead, 39-14 39-35 



The salt fused when dried at 110° C, and smelt slightly of the primary phosphine. It 

 dissolves readily in water. When its solution is concentrated by boiling it separates out 

 in oily drops. 



Attempts to prepare Benzyl Phosphinite of Copper. — The behaviour of benzyl 

 phosphinite of barium (or any other phosphinite) with acetate of copper is very character- 

 istic. On mixing the two solutions a pale green precipitate is produced in a strong 

 solution, but no precipitate in a weak solution. A specimen of the green precipitate was 

 prepared and analysed. 



