Malonate, alkyl

The reaction can be applied to allyl malonates. Alkylation of diallyl mal-onate (734) with bromoacetate and acetoxymethylation afford the mixed triester 735. Treatment of the tricster 735 with Pd catalyst affords allyl ethyl itaconate (736). In a similar way, a-methylene lactone and the lactam 737 can be prepared[462]. 

Sodium salt of diethyl malonate alkyl halide... 

Another metal-catalyzed microwave-assisted transformation performed on a polymer support involves the asymmetric allylic malonate alkylation reaction shown in Scheme 12.4. The rapid molybdenum(0)-catalyzed process involving thermostable chiral ligands proceeded with 99% ee on a solid support. When TentaGel was used as as support, however, the yields after cleavage were low (8-34%) compared with the corresponding solution phase microwave-assisted process (monomode cavity) which generally proceeded in high yields (>85%) [30],... 

Alkylation reactions of ketones and esters using 1 have been reported with good enantioselection. Free radical-mediated alkylation of a y-lactam proceeded with good enantioselection (eq 6). Malonate alkylation provides the 1,3-diphenyl allylation product... 

A potential side reaction in malonate alkylation is E2-elimination, which mainly depends on the structure of the alkyl halide. Also, dialkylation may occur if the malonate contains two active hydrogens. Dialkylation may be circumvented by carrying out the deprotonation with one equivalent of NaH. 

Combretazolone 22 was constructed via reaction of an appropriate a-hydroxyketone with PMB-isocyanate, subsequent cyclization and final removal of the PMB group in refluxing trifluoroacetic acid. Cyclopentenone analogues were prepared via sequential malonate alkylation-acylation followed by ring closure and decarboxylation. 

Naphthyridones 22, which are of interest as pharmacological preparations, have been synthesized by the reaction of vicinal aminopyridinecarbonitriles 23 with diethyl malonate. Alkylation of these products with ethyl monobromoacetate results in N-substituted compounds 24 (1990ZC20)... 

Alkylation of malonate anion Hernandez et al. [155, 156] have developed a rapid and easy procedure for the synthesis of C-labeled esters using a combination of solvent-free phase-transfer catalysis conditions and microwave technology. A detailed study of the first step, which consists in malonic alkylation, did not reveal any advantages of microwave activation compared with conventional heating (Eq. 71) ... 

Esters are much easier to work with than carboxylic acids, and a useful alternative procedure removes one ester group without having to hydrolyse the other. The malonate ester is heated in a polar aprotic solvent—usually DMSO—in the presence of sodium chloride and a little water. No acid or base is required and, apart from the high temperature, the conditions are fairly mild. The scheme below shows a dimethyl malonate alkylation (note that NaOMe is used with the dimethyl ester) and removal of the methyl ester. 

Condensation of 2-nitrosodiphenylamines with a variety of highly stabilized carbanions of dialkyl malonates, alkyl phenylacetates, and trialkyl phosphonoacetates is an efficient way for the synthesis of a great deal of substituted iV-arylquinoxalin-2 (l//)-ones (Scheme 101) [235, 236]. Double additions of anions of 2-cyanoalkyl carboxylates to 2-nitroso-4-alkylaminodiphenylamines result in the formation of pyrroloquinoxaUnones [236]. 

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