Jeffrey Yick-Pui. Mui

Halomethyl-metal compounds VIII. The reaction of phenyl(trihalomethyl)mercury compounds with hydrogen chloride

Abstract Dihalocarbenes (CCl2, CClBr, CBr2) obtained from the corresponding C6H5HgCXYBr compounds have been found to insert into the HCl bond giving haloforms, HCCl3, HCCl2Br and HCBr2Cl, respectively. In chlorobenzene solution at 80° C6H5Hg cleavage is a competing reaction which in the case of C6H5HgCBr3 accounts for 80% of the HCl consumed. The resulting CBr3HgCl introduces further complications, since CX2 insertion into the HgCl bond occurs, giving HgCX2Br compounds which are sources of carbenes other than those derived from the starting mercurial. At room temperature only the C6H5Hg cleavage reaction is observed, and this allowed preparation of pure ClHgCCl3, ClHgCCl2Br, ClHgCClBr2 and ClHgCBr3. The action of methanolic HCl on C6H5HgCCl3 produces phenylmercuric chloride and chloroform; a possible explanation for this marked solvent effect is presented.