Carbonyl-trithiane

This name applies to formation of 5. Names for formation of 6,7, and 8, are, respectively, thioxo-de-oxo-bisubstitution, dimercapto-de-oxo-bisubstitution, and carbonyl-trithiane transformation. 

Compounds with active hydrogen add to the carbonyl group of acetone, often followed by the condensation of another molecule of the addend or loss of water. Hydrogen sulfide forms hexamethyl-l,3,5-trithiane probably through the transitory intermediate thioacetone which readily trimerizes. Hydrogen cyanide forms acetone cyanohydrin [75-86-5] (CH2)2C(OH)CN, which is further processed to methacrylates. Ammonia and hydrogen cyanide give (CH2)2C(NH2)CN [19355-69-2] ix.orn. 6<55i the widely used polymerization initiator, azobisisobutyronitrile [78-67-1] is made (4). 

The procedure described here provides a convenient route to aldehydes with trithiane serving as an inexpensive, masked carbonyl group.2-4 The reaction is limited, however, to the use of primary alkyl halides, aldehydes, and ketones for elaboration of the carbon chain through attack on the metallated trithiane. Examples of aldehydes synthesized by this method are given in Table I. 

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. 

Various dithiaheterocyclic compounds fragment unsymmetrically in the presence of iron carbonyls to form bridging dithiolate ligands as in 172 (Table II). In contrast, UV irradiation of dithiane or trithiane in the... 

Similarly, the dynamic behavior of the complex [Ir3Rh(CO)6)/i2-GO)3(/t3-l,3,5-trithiane)] was studied by variable temperature H and NMR spectroscopy and also by 2-D exchange spectroscopy (EXSY) NMR spectroscopy <1994HCA1869>. However, only the apical and basal carbonyl groups are involved in the intramolecular flexibility of the system and not the 1,3,5-trithiane moiety. 

Another aspect of these complexes concerns fluxional processes in solution (ring interconversion of 1,3,5-trithiane moieties, pyramidal S-inversion, merry-go-round fluxional behavior of carbonyls in the complex, etc.). These have been studied often by 2-D EXSY NMR spectroscopy (e.g., <1983ICA(72)201>). 

Tris(triphenylphosphine) rhodium carbonyl hydride 1,3,5-Trithiane Trithiocarbonicacid... 

The tetranuclear iridium cluster [Ir4(CO)4(l,3,5-trithiane)] exists as two isomers, one possessing a bridging carbonyl ligand and the other not. The unbridged isomer is discussed as an intermediate in a merry-go-round isomerization process. The pentanuclear clusters [MIr4(CO)7(/i-CO)2 L(>/ -C5Me5)(/i4-PPh)] (M = Rh, Ir L = CO) have square-pyramidal metal... 

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