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Mercaptan: any
of a class of organosulfur compounds is similar to the alcohol and phenol but
containing a sulfur atom in place of the oxygen atom. Compounds containing -SH
as the principal group directly attached to carbon are named 'thiols'. In
substitutive nomenclature their names are formed by adding '-thiol' as a suffix
to the name of the parent compound. When -SH is not the principal group, the
prefix 'mercapto-' is placed before the name of the parent compound to denote an
unsubstituted -SH group. 'thio' is a chemical prefix indicates the replacement
of an oxygen in an acid radical by sulfur with a negative valence of 2. Sulfur
analog of alcohol is called thiol (or mercaptan), and ether analog is called
sulfide.
Thiodiglycol
provides versatile solvency characteristics with both polar and non-polar
properties. It is used as a solvent in
dyeing
textile and coating ways. It is used as a building block to produce corp protection products, dispersants, fibers, plasticizer, rubber
accelerator, pesticides,
dyes, and other organic compounds. It is used as a chain transfer agent in the manufacture of polymer.
Sulfate (also
spelled sulphates in Euorpe) is any chemical compound related to sulfuric acid,
formed by replacing one or both of the hydrogens with a metal or a radical.
Sulfite is any salt of sulfurous acid, chemical species
H2SO3, which is formed in
aqueous solutions of sulfur dioxide. Sulfurous acid is a clear liquid with a
strong sulfur aroma. Sulfide is a compound having one or more sulfur atoms in
which the sulfur is connected directly to a carbon, metal, or other nonoxygen
atom; for example, sodium sulfide, Na2S. Sulfur compounds
are used in the synthesis of medicine and chemicals, manufacture of wood, pulp
and paper. They are used in winemaking, brewing, food preservation, metallurgy,
engraving process, ore flotation, additive in making steel, bleaching, metal
treatment and as an analytic reagent.
The first
chemical contrast of thiols and sulfides with alcohols and ethers is acidity
which is important in organic reactions. Thiols are stronger acids than relevant
alcohols and phenols.Thiolate conjugate bases are easily formed, and are
excellent nucleophiles in SN2 reactions of alkyl halides and tosylates. The
nucleophilicity of sulfur is much greater than that of oxygen, resulting in a
number of useful electrophilic substitution reaction that are rare by oxygen.
For example, sulfides form (with alkyl halides) ternary sulfonium salts, in the
same alkylattion of tert-amines quaternary ammonium salts, whereas ternary
oxonium salts are prepared only under extream conditions. Without exception,
sulfoxides, sulfinate salts and sulfite anion also alkylate on sulfur, despite
of the partial negative formal charge on oxygen and partial positive charge on
sulfur. The second character is the oxidation states of sulfur. Oxygen has only
two oxidation states, whereas sulfur covers from –2 to +6 as follows:
- -2: Hydrogen
Sulfide (H2S), sulfides,
sulfonium ions
- -1:
disulfides
- 0: S
elemental, sulfoxides, sulfenic acids
- +2:
sulfones, sulfinic acids
- +4: sulfonic
acids, sulfite esters
- +6: sulfate
esters
Information
for glycol.
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