Studies on the reactivity of methyl γ-tosylcrotonoate as ambident reagent in organic synthesis

✍ Scribed by Francisco Caturla; Carmen Nájera

• Book ID: 104207346
• Publisher: Elsevier Science
• Year: 1996
• Tongue: French
• Weight: 961 KB
• Volume: 52
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(96)00929-5

✦ Synopsis

The treatment of methyl (@A-tosyl-2-butenoate (4) with hvo equiv. of sodium hydride and different mono and dihalides gives mainly y,y-and a,a-or a,y-and a,a-dialkylated products (5-7) depending on the electrophile. The corresponding monoanion dimerizes with iodine to afford stereoselectively diiethyl cisA,Sditosyl-2&cyclohexadiene-1,2dicarboxylate (11). The tosyl group in compounds 6 and 7 is reduced and in the case of y,y-dimethylated 5a substituted by sodium diielhyl malonate under Pd(PPh& catalysis. Michael addition of different nucleophiles provides the corresponding ~-substituted methyl y-tosylhutanoates 16.