C decarbalkoxylative

Sodium acetate/acetic anhydride Preferential C-decarbalkoxylation COOR H... 

Banks (151) has reported the decarbalkoxylation (NaCl in wet DMSO at 148-153°C) of the geminal diesters 490 and 493. He found that the reaction of 490 was highly stereoselective yielding the axial isomer 491 in preference to the more stable equatorial isomer 492 (ratio =9 1). On the other hand, the reaction of 493 was non-stereoselective (ratio =1 1 of 494 and 495). 

C-De-tert-butylation, preferential 31, 78 Decarbalkoxylation s. a. Replacement of carbalkoxy groups by hydrogen C-Decarbalkoxy ation 29, 499s31 -, ring closure with - 17, 902 Decarbonylation... 

Arylsulphenylation of 1,3-dicarbonyl compounds cm be effected at room temperature in an Et4N+ F" emulsion, but dianions R CHCOCHCOR, formed by successive treatment with NaH and Bu"Li, are sulphenylated at the alternative site by RbSSPh. 8-Keto-esters, malonates, and a-cyanoalkanoates can be sulphenylated and decarbalkoxylated in a one-pot process by reaction at 150—160 C, in HMPA, with PhSSPh and Nal, providing a-(phenylthio)alkyl ketones, cp(phenylthio)alkanoates, and tf-cyanoalkyl phenyl sulphides. 

C-Decarbo-tert-butoxylation —, partial 17, 134 N-Decarbalkoxylation (s. a. N-Decarbobenzoxylation)... 

Lithium chloride I hexamethylphosphor amide Decarbalkoxylative C-alkylation... 

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