Malonate groups

Reactions on SP2 Type Unsaturated Systems Very few studies have been carried out on the stereochemistry of the Michael reaction. However, Abramovitch and Struble (36) have found that compound 101 was the main product when diethyl sodiomalonate (free of ethoxide ion and ethanol) was added to 4- t-butyl-1-cyano cyclohexene (99) in boiling toluene. This result can be rationalized by axial attack on 99 to give first 100 having a chair-like conformation which is then transformed into 101 by internal trapping (see arrow). However, when the addition of diethyl malon-ate anion was carried out in ethanol under thermodynamically controlled conditions, product 103 with an equatorial malonate group was obtained, presumably via the twist-boat intermediate 102. 

Two types of malonate groups have been identified with one in a six-membered chelate ring and the other in a non-chelated form [166]. 

Michael addition of benzenethiolate to 4-f-butyl-l-cyanocyclohexene gives only products containing an axial PhS group the same result was obtained from ethyl 4-r-butylcyclohexene-l-carboxylate. In contrast, the addition of diethyl sodiomalonate gave only the equatorial malonate group under thermo-... 

The aminomethylenemalonates can be cyclized at high temperature as in the formation of pyrido[3,2-. With the aminomethylene-malonate group in the 4-/6-position in a free 2-pyrimidinone, cyclization is to the adjacent ring nitrogen <82JHC1581>. 

For the malonate group to be used for fatty acid synthesis, it must first be transferred from malonyl-CoA to malonyl-ACP by the 32.4-kDa monomeric malonyl-CoA ACP transacy-lase, the product of the fabD gene (Fig. 2). A stable malonyl-serine enzyme intermediate is formed during the course of the FabD reaction, and subsequent nucleophilic attack on this ester by the sulfhydryl of ACP yields malonyl-ACP. The high reactivity of the serine in malonyl-ACP transacylase is due to the active site being composed of a nucleophilic elbow as observed in alpha/beta hydrolases. The serine is hydrogen bonded to His-201 in a fashion similar to serine hydrolases. 

Conjugate nucleophilic addition of methyl, vinyl, allyl, and malonate groups to l-(2-indolyl)but-2-enecarbonitrile has been effected with a range of organometallic carbanions, for example, the lithium derivative of ethyl vinyl ether gives the product (390), which can be cyclized to a pyrrolof 1,2-ajindole (391) (Scheme 130) <9ITL7237>. 

The heteroleptic ruthenium dye (347) which was utilized both as a sensitizer component and a molecular bridge to connect metal oxide particles in a metal oxide semiconductor has been designed by Youngblood and co-workers. Phosphonates have been found chemically selective for Ti02 and the malonic groups selective for Ir02 H20. 

The synthesis of an EPSP synthase inhibitor 91, vdiich relies on a malonate group to mimic a phosphate group, has been reported and the EPSP analogue 92 has been prepared to study inhibition of EPSP synthase. "... 

An arylmethylmalonate derivative, with an ortho iodine substituent on the aromatic ring, undergoes a carbonylative cycliza-tion by oxidative addition to the aryl iodide and reaction at the nucleophilic center of the malonate group. ... 

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