Malonate derivatives

In a similar reaction the bis-tosylate shown below was to be converted into a bis-malonate derivative. In this cyclic derivative both groups are hold closely together and intramolecular reactions proved to be so much faster than intermolecular substitution under all ex-... 

The three isomers of thiazoleacetic acid can be decarboxylated, the order of facility being 2>5>4, though the relative stability depends on each particular compound and the reaction conditions (72-75). This reaction may be used to obtain certain alkylthiazoles (73). Malonic derivatives can also be decarboxylated to give aliphatic thiazole acids (49, 51)... 

FLUORINECOMPOUNDS,ORGANIC - FLUORINATED AROMATIC COMPOUNDS] (Volll) -malonate derivative TALONIC ACID AND DERIVATIVES] (Vol 15)... 

Pd-catalyzed asymmetric allylic alkylation is a typical catalytic carbon-carbon bond forming reaction [ 126 -128]. The Pd-complex of the ligand (R)-3b bearing methyl, 2-biphenyl and cyclohexyl groups as the three substituents attached to the P-chirogenic phosphorus atom was found to be in situ an efficient catalyst in the asymmetric allylic alkylation of l-acetoxy-l,3-diphenylprop-2-en (4) with malonate derivatives in the presence of AT,0-bis(trimethylsilyl)acetamide (BSA) and potassium acetate, affording enantioselectivity up to 96% and quantitative... 

An alternative is the strategy outlined above for (20) via (21), Since the two enolates needed are the same, a malonate derivative supplies them both and in practice cyanoester (30) is the most convenient. The version with ammonia to trap the intermediate as (31) i he Guaresci reaction. 

The chiral center would be installed from either Unear carbamate 15 or branched carbamate 16 via the asymmetric addition of malonate anion to the 7i-allyl Mo complex reported by Trost et al. [11] to afford the branched chiral malonate derivative 17. Decarboxylation of 17 should provide the mono-carboxylic acid 18. Masa-mune homologation with 18 affords our common precursor 14. Linear carbamate 15 was obtained from the corresponding cinnamic acid, and branched 16 was prepared in one pot from the corresponding aldehyde. 

The complexation of other mixed oxa aza macrocycles has been studied, and protonation and stability constants of the zinc complexes of macrocycles l,4,10,13-tetraoxa-7,16-diazacycloocta-decane-7,16-bis(malonate), the -7-malonate derivative and -7,16-bis(methylacetate) derivative have been determined by potentiometry at a 1 1 ligand-to-metal ratio.730... 

The very first report on the use of ionic liquids as soluble supports was presented by Fraga-Dubreuil and Bazureau in 2001 [102]. The efficacy of a microwave-induced solvent-free Knoevenagel condensation of a formyl group on the ionic liquid (IL) phase with malonate derivatives (E1CH2E2) catalyzed by 2 mol% of piperidine was studied (Scheme 7.89). The progress of the reaction could be easily monitored by 1H and 13C NMR spectroscopy, and the final products could be cleaved from the IL... 

Previous work [111] by our group has demonstrated that RTIL-catalyzed 1,3-dipolar cycloaddition under the action of microwave irradiation leads to dramatically shorter reaction times with better yields of isolated products. We have recently investigated the reactivity of the formyl group covalently grafted on the ionic liquid phase 75 in the Knoevenagel reaction with malonic derivatives 76 [112], as shown in Scheme 8.76. 

The addition-elimination adducts (143)-(145) are also useful precursors to imidazo[4,5-b]pyridines. Thus, the malonate derived products (143) on treatment with hot ethanolic HC1 [92JCS(P1)2789] or hot ethanolic triethylamine (78H241) gave the imidazo[4,5-b]pyridones (157). The dinitrile derivatives (144) gave the ortho amino nitriles (158) by treatment with hot methanolic sodium hydroxide solution and the nitrile esters (145)... 

Based on these reactions, Imada et al. reported the first enantioselective alkylation of 2,3-alkadienyl phosphates 96 by employing malonate derivatives 97 in the presence of palladium complex catalysts bearing MeOBIPHEP or BINAP as ligand (Scheme 14.21) [49]. The highest enantioselectivity (90% ee) was obtained by the catalyst combination Pd2(dba)3-CHC13 and (R)-MeOBIPHEP. 

Isopropylidene malonate derivatives (501) were boiled in a mixture of... 

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