Carbanions synthesis

Acylation of oc-sulphinyl carbanions. Synthesis of fS-oxosulphoxides. oi-Ketosulphoxides have found very broad application in organic synthesis (see, for example. Reference 532). For this reason, a great deal of examples of their syntheses appear in the chemical literature. The main approach to this class of functionalized sulphoxides involves the reaction of a-sulphinyl carbanions with carboxylic esters or acyl halides. 

Patois, C., Ricard, L., and Savignac, P., 2-Alkyl-5,5-dimethyl-l,3,2-dioxaphosphorinan-2-ones a-lithiated carbanions. Synthesis, stability, and conformation, J. Chem. Soc., Perkin Trans. 1, 1577, 1990. 

Teulade, M.-P., Savignac, P., Aboujaoude, E.E., and Collignon, N., a-Lithiated phosphonate carbanions. Synthesis, basicity and stability to self-condensation, J. Organomet. Chem., 312, 283, 1986. 

The p-halogenotetradecachlorotriphenylmethyl radicals. In the carbanion synthesis of the radical HOCO—PTM- from HOCO—PTM—H in the conventional manner, the radical I—PTM- is a minor by-product. It appears that the intermediate dianion OCO—PTM reacts rapidly with iodine, giving the radical OjC—PTM- (Ballester ct a/., 1982b Ibanez, 1972). High concentrations of iodine and/or long reaction times cause the formation of the radical I—PTM- as a major product by oxidative decarboxylation. It has been found that the dianion "O2C—PTM is stable under the reaction condition (Ballester et al., 1982b Ibanez, 1972). These results may be accounted for as shown in (142) through the intermediacy of acyclic,... 

Sulphinyl and Sulphiliminyl Carbanions Synthesis and Properties.—The carbanion carbons in a-lithiothian l-oxide and PhS(0)CH2Li have been found by n.m.r. spectroscopy to be nearly planar (sp -hybridized), presumably due to a chelated structure such as (68). Interest... 

H. Tanaka, M. Fukui, K. Haraguchi, M. Masaki, and T. Miyasaka, Cleavage of a nucleosidic oxetane with carbanions Synthesis of a highly promising candidate for anti-HIV agents. A phosphonate isostere of AZT-5 -phoshate, Tetrahedron Lett. 30 2567 (1989). 

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