Mercury captans

Thiols have a marked ten dency to bond to mercury and the word mercaptan comes from the Latin mer curium captans which means seizing mercury The drug dimercaprol is used to treat mercury and lead poisoning It IS 2 3 dimercapto 1 propanol... 

Mercaptans were discovered in 1834 by W. C. Zeise (pp. 930, 1167) who named them from the Latin mercurium captans, catching mercury. 

Thiols, unlike alcohols, form insoluble salts (mercaptides) (4) and (5) by reaction with heavy metals like mercury and lead (Scheme 3) this is the origin of the former name mercaptan for thiols, which comes from the Latin mercurium captans, meaning mercury seizing. In modern nomenclature the name thiol is preferred to mercaptan although the prefix mercapto is still allowed for the unsubstituted SH radical. 

Mercaptans may be considered as monosubstitution-products of hydrogen sulphide, C2H5.SH, just as the alcohols are considered as derivatives of water, C2H5.OH. They are sometimes called thio-alcohols. The name mercaptan was originally given to the members of this class on account of the fact that they form compounds with mercury. The name is derived from the Latin words mevcurium captans. Ethyl mercaptan is a typical... 

The name mercapto is derived from the fact that thiols were once called mercaptans. This terminology was abandoned by lUPAC several decades ago, but old habits die hard, and many chemists still refer to thiols as mercaptans. The term is derived from the Ladn mercurium captans (capturing mercury) and describes the abiUty of thiols to form complexes with mercury as well as other metals. This abihty is put to good use by the drug called dimercaprol, which is used to treat mercury and lead poisoning. 

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