Reaction of Metallated Acetylenes with a-Haloethers

Reactions of polar organometallic and Grignard reagents with a-haloethers generally proceed much more easily than the familiar SN2 displacements with alkyl halides. This may be explained by the large extent of Sjql character due to the ionization  

For reasons discussed below, a successful performance of this procedure requires a considerable experimental skill at the various stages. 

The isolation procedure is analogous to the one in exp. 1. During the extraction, problems may be encountered with the separation of the organic and aqueous layer. This is 

It is a reasonable assumption that with the nucleophiles NH2 and NH3 some displacement on methylene carbon occurs with formation of CICH2CSCCH2NH2 or Ni CHjCsC-CH2NH2, compounds which have good water-solubility. 

In the last stage of the disrillative separation of the products from the solvent, some 2,4-hexadiyne solidifies in the condenser. This may be the result of one (or both) of the following reactions  

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