532 



PROF. LETTS AND MR R. F. BLAKE ON 



been investigated. They readily combine with alkyl iodides, giving hydriodates of 

 tertiary phosphines. 



General Properties of Tertiary Phosphines. 



The following tertiary bases have been obtained : — 



Name. 



Condition. 



Boiling Point. 



Trimethyl phosphine ( 1 ), 



Liquid. 



40-42 



Tri-ethyl 



( 2 ), 





)> 



127 



Tri-isopropyl „ 



( 3 )> 





>> 



? 



Tri-isobutyl „ 



( 4 ), 





» 



215 



Tri-isoamyl „ 



( 5 ), 





)> 



about 300 



Tri-phenyl „ 



( 6 )> 





Solid. 



above 360 



Ethyl-isopropyl-isobutyl „ 



0. 





Liquid. 



about 190 



Methyl-diphenyl „ 



( 8 ), 





>» 



284 



Ethyl-diphenyl „ 



<•>, 





j» 



293 



Di-ethyl-phenyl „ 



( 10 )> 





>> 



220 



Di-methyl-ethyl „ 



< u ). 





» 



83-85 



Di-ethyl-methyl „ 



( 12 >, 





» 



110-112 



Di-ethyl-propyl „ 



e 3 ), 





j> 



146-149 



Di-ethyl-isoamyl „ 



( u ), 





» 



185-187 



Di-ethyl-benzyl „ 



( 15 ), . 





» 



252-255 



Ethyl-dibenzyl „ 



( 16 ;, . 





» 



320-330 



Dimethyl p. tolyl „ 



( 17 ), 





» 



210 



Di-ethyl p. tolyl „ 



( 1S ), • 





>! 



240 



Dimethyl xylyl „ 



o, . 





» 



230 



Diethyl xylyl 



( 20 )> • 



» 



260 



( J ), ( 2 ) Hofmann and Cahotjrs, Amu de Chim. unci dc Phys., 3, vol. li. p. 35. 



( 3 ), ( 4 ). ( 5 ) Hofmann, BericMe, vi. (1873) pp. 292 and 304. ( 6 ) Michaelis, Beriehte, xv. (1882) p. 801a. 



( 7 ) Hofmann, Beriehte, vi. (1873) p. 304. ( 3 ) Ibid. Annalen, 181, p. 345. 



( 9 ), ( 10 ) Michaelis and Link, Annalen, 107, p. 210. 



( n ). ( 12 ). ( 13 ), ( 14 )» ( 16 ), ( 16 ) Collie, Chem. Soc. Jour., 1888, p. 714. 



( 17 ), ( 18 ). ( 19 ), ( 20 ) Czimatis, Beriehte, xv. (1882) 2014. 



The tertiary phosphines hitherto obtained are, with the exception of triphenyl 

 phosphine, liquids at ordinary temperatures, having a powerful odour. They are 

 insoluble in water, but soluble in ether, &c. As a rule, they oxidise rapidly in contact 

 with the air, fuming and growing hot, and in some cases igniting spontaneously. The 

 product of this oxidation is a tertiary phosphine oxide of the formula R 3 PO, and no 

 doubt of the constitution 



E-)P=0. 



The final products of the oxidation of phosphuretted hydrogen, and of primary, 

 secondary, and tertiary phosphines are therefore respectively — 



H 3 P0 4 

 RH 2 P0 3 

 R 2 HP0 2 

 R 3 PO. 



