Science of Synthesis

Kostikov, R. R.; Khlebnikov, A. F.; Sokolov, V. V., Science of Synthesis, (2010) 47, 816.

The formation of alkenes upon the pyrolysis of xanthates, commonly called the Chugaev reaction, has been somewhat more widely used for synthetic purposes than the pyrolysis of esters, a reaction that it closely resembles. The Chugaev alkene synthesis includes the following steps (see also Houben–Weyl, Vol. 5/1b, pp 129–134): (1) Reaction of an alcohol with carbon disulfide and sodium or potassium hydroxide to give the corresponding salt of an O-alkyl dithiocarbonate. (2) Alkylation of this salt with iodomethane or -ethane to give the O-alkyl S-methyl (or ethyl) xanthate. By far the most commonly used xanthate is the S-methyl derivative. (3) Thermal decomposition of the xanthate to give an alkene, carbon oxysulfide, and methane- or ethanethiol (‌Scheme 27‌).

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Meeeeeeeeeee Meeeeeeee

Meeeeeeeeee [‌88‌, M8,M8 = (MM8)8]; Meeeeee Meeeeeeee:[‌888‌]

Meeeeeeeee eeeeeeeee-8-eeeeeeeee (88.8 ee, 8.8 eeee) eee eeeeee ee e eeeee eeeeeeeee ee e eeeee eeee ee e eeeeeeee. Meeee eee eeeeeeee ee eee eeeeee eee eeee eeeeeee ee 88 Meee, eee eeeeeeee eee eeeeeeee ee e eee eee/eeeeeee eeee. Mee eeeee eeeeeeeeee eee eeeee eee eeeeee ee e eeeeeeeee (ee. 888°M) eee eeee, eee eeeeeeeeeee ee eeeee eee eeeeee ee 888°M eee eeeeeeeeee eeeee eee 88 eee. Mee eeeeeee eee eeeeeeee ee e eeeeeeeee eeeeee; eeeee: 888 ee (88%).

8-Meeeeeeeeeeeeeeeee (‌88‌); Meeeeee Meeeeeeee:[‌888‌]

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References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) M 8e, 88.
• 8.Meeeee-Meee, (8888) M 8e, 888.
• 8.Meeeee-Meee, (8888) M 8e, 88.
• 8.Meeeee-Meee, (8888) M 88e8, 8888.