Sym.-TRiTHiANE

ALDEHYDES FROM PRIMARY ALCOHOLS BY OXIDATION WITH CHROMIUM TRIOXIDE 1-HEPTANAL, 52, 5 ALDEHYDES FROM sym-TRITHIANE n-PENTADECANAL, 51, 39 Aldehydes, acetylenic, 54, 45 Aldehydes, aromatic, 54, 45 Aldehydes, benzyl, 54, 45 Aldehydes, olefinic, 54, 45... 

The crude tetradecyltrithiane contains 4-6% of sym-trithiane and melts at 69-71°, recrystallization (Note 6) gives pure product, m.p. 76.3-76.6°. 

Tetradecyl-sym-trithiane, by reaction of 1-bromotetradecane with sym-trithiane in presence of -butyl-lithium, 51,39... 

It is essential that the sym-trithiane be of good purity. Commercial sym-trithiane can be purified by extraction from a thimble in a hot extractor using 300 ml. of toluene for 30 g. of trithiane. After cooling the extract to 0°, sym-trithiane is recovered by filtration and recrystallized from toluene. In one run the checkers used sym-trithiane as obtained from Eastman Organic Chemicals and observed a 10% decrease in yield of mpentadecanal. 

A considerable number of electrophiles were used, and the dithiane route found great utility for the syntheses of simple monofunctional compounds as well as for polyfunctional molecules, for which the dithiane moiety affords an invaluable temporary protection of a future carbonyl group. Some experimental procedures published in Organic Syntheses — cyclobutanone [277] and 3-hydroxy-l-cyclohexene-l-carboxaldehyde [278] — are illustrative. A similar route to aldehydes [279] makes use of sym-trithiane as a formyl anion equivalent. 

Sym-Trithiane is made as described by Bost and Constable and is used without purification. It can be purchased from Aldrich Chemical Company, Inc. 

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