Acetylene derivs monochloride

Reactions of acetylene derivs. with selenium monochloride 3-Chlorobenzo[b]selenophenes... 

Diynes. A general method for preparation of 1,3-diynes, particularly terminal ones, involves palladium-catalyzed coupling of alkynylzinc derivatives with (E)-l-iodo-2-chloroethylene. This alkene is obtained in 83% yield by reaction of acetylene with iodine monochloride in 6 A HCI. Coupling results in a l -chloro-1,3-cnync (1), which is converted into a l-sodio-l,3-diyne (2), which in turn can be reduced or alkylated to give a 1,3-diyne. 

The method of making lewisite was suggested by the analogous method of mustard-gas manufacture used by the Allies. Thus, mustard is formed by the action of ethylene on sulfur monochloride, while lewisite is produced by action of acetylene on araeme trichloride in the pieaenct of aluminum trichloride acting as a catalyst. The dark brown viscid liquid a hich results from this latter reaction is decomposed by treatment with hydrochloric acid at O C. (32 F.), and an oil is obtained which < an be fractionated by distillation in vacuo into three chlor inyl derivatives of arsenic trichloride. These derivatives, which differ from each other only by the successive addition to the arsenic trichloride of one, two, or three molecules of acetylene, are as follows (see Chart Xlll) ... 

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