Hexa chloroacetone

Carbon tetrachloride - CC14 (///) Deutero chloroform - CDC13 (z v) Hexa chloroacetone - CC13 - CO-CCl3... 

Triphenylphosphine dichloride exhibits similar reactivity and has been used to prepare chlorides.18 The most convenient methods for converting alcohols to chlorides are based on in situ generation of chlorophosphonium ions19 by reaction of triphenylphosphine with various chlorine compounds such as carbon tetrachloride20 and hexa-chloroacetone.21... 

Reliable clean S 2 reactions with secondary allylic alcohols can be achieved only with Mitsunobu chemistry. Here is a well-behaved example with a Z-alkene. The reagents have changed since your last encounter with a Mitsunobu-type reaction instead of DEAD and a carboxylic acid we have hexa-chloroacetone. 

Reactions of benzene solutions of arylalkynes with 1 equiv. of chloroacetone and 2 equiv. of Et.iN, using a mixture of (PPhsjaPd and Cul as a catalyst, afford 1,4-diarylbutadiynes in very good yields. Under similar reaction conditions aliphatic 1-alkynes yield a mixture of symmetrically disubstituted 1,4-dialkynyl-l,3-butadiynes and 3-alkyl-4(l-alkynyl)-hexa-l,5-diyn-3-enes (10 equations 15 and 16). 7 This method may represent a good alternative, in nonpolar organic solution, to the Glaser reaction. 

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