Dimethyl malonate anion

Alkylation of allylic acetates (formates or chlorides) with the dimethyl malonate anion is catalyzed by sodium tricarbonyl(nitroso)iron90. The nucleophile attacks the less hindered site... 

The carbanion derived from dimethyl malonate reacts with the cyclic nitro compounds 422 of ring size 5, 6, 7, 8 and 12 to afford the corresponding esters 423. Acyclic allylic nitro compounds 424 (R = Me, CH2OAC or CC Et) are attacked by bulky nucleophiles, such as dimethyl malonate anion, mainly at the terminal primary carbon atom to give rearranged products 425, whereas smaller nucleophiles, e.g. the anion derived from methyl cyanoacetate, react at the tertiary carbon atom to yield 426409a 453 455. 

The co-ordinated double bond in PtCl2(vp) (79) is susceptible to nucleophilic attack by class "a nucleophiles to form Pt(II)-carbon tr-bonded complexes such as that in Fig. 19 b (other nucleophilic groups giving similar products include alkoxides, nitromethide anion and dimethyl malonate anion). The C-bonded nucleophilic groups are solvolysed by alcohols to the alkoxy derivatives. 

Stereoselective allylic alkylations have been carried out with the aid of palladium catalysts. The 17-(Z)-ethylidene groups of steroids (obtained from the ketones by Wittig olefination) form n-allyl palladium complexes in the presence of copper(n) salts (B.M. Trost, 1974, 1976). Their alkylation with dimethyl malonate anions in the presence of 1,2-ethane-diylbis[diphenylphosphine] (— diphos) gives a reaction exclusively at the side chain and only the (20S) products. If one starts with the endocyclic 16,17 double bond and replaces an (S)-20-acetoxy group by using tetrakis(triphenylphospbine)palladium,the substitution occurs with complete retention of configuration, resulting from two complete inversions (B.M. Trost, 1976). 

The second step in this sequence, illustrated below, is a 1,2-addition reaction between a dimethyl malonate anion and 2-naphthaldehyde. The mechanism for 1,2-addition reactions was discussed in detail in Chapter 7. In order for this reaction to proceed, it is important to use a base that is sufficient to deprotonate the methylene group of dimethyl malonate. Furthermore, it is important to use a base that will not hydrolyze the methyl esters. Sodium hydride is generally sufficient to affect this deprotonation. 

The precursor 130, which was prepared using a combined YNSat-SnAt three-component reaction, has been employed in a route toward the 3-aryloxindole derivative 131 (Equation 36) <2004OL4957>. Similar reductive annulations of intermediates derived by nucleophilic displacement of an immobilized aryl fluoride with dimethyl malonate anions, eventually providing 1,2-dialkoxyindole derivatives, have been described previously <2003OL2935>. 

The reaction conditions were later optimized by Danishefsky and coworkers in the condensation of bromoarene 34 with dimethyl malonate anion, where the... 

In the total synthesis of fredericamycin A reported by Kita et al, the condensation of dimethyl malonate anion with aryne 36 was used to construct the AB-ring system. The intermediate homophthalic esters 37 and 38 were thus obtained in a 58% combined yield with a modest regioselectivity (2 3) (Scheme 12.14) [32]. 

Scheme 83 The reaction of dimethyl malonate anion with carbon disulfide leading to a 3,4-dihydroxythieno[2,3-b]thiophene [130]...

C 3 branched species.Reaction of the S -ether of alkenyl selenone (86) with dimethyl malonate anion gave the cyclopropane (122) a similar reaction, but with D-/yxo-specificity, occurred with nitromethane.105... 

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