Depto. Química Orgánica

NOMENCLATURE AND PROPERTIES OF SULFUR COMPOUNDS

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15/07/2017
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The corresponding sulfur compounds to alcohols and ethers are thiols and thioethers - sulfides -, respectively.
WaterMethanolDimethylether
Hydrogen sulfideMethylthiolDimethylsulfide
Image However, dimethylsulfide displays a higher b.p. than its oxygen homolog.
This should be a consequence of the larger size and polarizability than oxygen.
No hydrogen bonding is possible.
The S-H···S hydrogen bond is weaker than the O-H···O.

The lower b.p. of hydrogen sulfide and methylthiol as compared to water and methanol, respectively, is proof of that.
Some simple examples of nomenclature:
Image
Thiols  are more acidic than alcohols:
Image
Sulfur is larger than oxygen and thus more capable to delocalize the negative charge.
Therefore, the sulfide anion is more stable and hence less basic than the corresponding alkoxide.