Allene-1,3-dicarboxylate

If two equivalents of the reagents are used, disubstitution to ECeC-CH(E)R occurs in most cases, but interestingly the reaction of LiCeCCH(Li)R with an excess of COj gives mainly the allenic dicarboxylic acids. These are probably the result of a rapid isomerization of the primary dilithium salt of the acetylenic diacid during the work-up or during the reaction of the dilithio compound with COj ... 

Scheme 4.7S Synthesis of a chiral allene dicarboxylate 288 through asymmetric transformation (DMC= 2-chloro-l,3-dimethylimidazolinium chloride).

Chiral Lewis acids are also applicable in the deracemization of racemic allene dicarboxylates 289. Treatment of dimethylallene-l,3-dicarboxylate 289 with a chiral organoeuropium reagent, (+)-Eu(hfc)3, gave the corresponding optically active allene in 79% ee (Scheme 4.76) [118]. Unfortunately the chiral allene could not be isolated from the reaction mixture without loss of its optical purity. 

In Scheme 63, four further examples of 1,5-diazocines obtained from 1,3-propanediamine derivatives are outlined, although only one was reported in good yields. Thus, iV-(2-aminoethyl)-l,3-propanediamine reacted with methyl allene dicarboxylate to give the diazepinodiazocine 79 in which the double bond can be located either on the diazocine ring or in the diazepine nucleus <1995H(41)1709>. 

Trapp, O., Schurig, V. Novel direct access to enantiomerization barriers from peak profiles in enantioselective dynamic chromatography enantiomerization of dialkyl-1,3-allene-dicarboxylates, Chirality, 2002, 14, 465-470. 

Penta-2,3-diendioic acid 1,3-allene-dicarboxylic acid) (71) Total electron density 367, 368,... 

The first allenic dicarboxylic acid, named glutinic acid (2,3-pentadienedioic acid) was isolated from Alnus glutinosa (Betulaceae). 

A. 3-Methylenecycldbutane-l,2-dicarboxylic anhydride. A 2-1. stainless steel autoclave equipped with stirrer, pressure gauge, and thermocouple is charged with 500 g. (5.1 moles) of maleic anhydride, 645 ml. of benzene, and 0.25 g. of hydroquinone. The autoclave is closed, cooled to — 70° with stirring, and evacuated to a pressure of about 20 mm. Allene (100 g., 2.5 moles) (Note 1)... 

Since 3-methylenecyclobutane-l,2-dicarboxylic anhydride is easily converted to 3-methyl-2-cydobutene-l,2-dicarboxylic acid, it is an intermediate to a variety of cyclobutenes. The dimethyl ester of 3-methylenecyclobutane-l,2-dicarboxylic acid is also a versatile compound on pyrolysis it gives the substituted allene, methyl butadienoate, and on treatment with amines it gives a cyclobutene, dimethyl 3-methyl-2-cyclobutene-l,2-di-carboxylate. ... 

The first synthesis of derivatives (77) of pentatetraene-carboxylic acid has been reported using a Wittig reaction of 1-H-allene-l,3-dicarboxylate monoester chlorides (76) in the presence of triethylamine.60 In one case an intermediate was obtained and was converted to (77) by further treatment with base. The reaction of carbon suboxide with phosphonium ylides has also... 

The kinetic resolution using a chiral zirconocene-imido complex 286 took place with high enantioselectivity to result in chiral allenes 287 (up to 98% ee) (Scheme 4.74) [116]. However, a potential drawback of these methods is irreversible consumption of half of the allene even if complete recovery of the desired enantiomer is possible. Dynamic kinetic resolutions avoid this disadvantage in the enantiomer-differentiating reactions. Node et al. transformed a di-(-)-L-menthyl ester of racemic allene-l,3-dicarboxylate [(S)- and (RJ-288] to the corresponding chiral allene dicarbox-ylate (R)-288 by an epimerization-crystallization method with the assistance of a catalytic amount of Et3N (Scheme 4.75) [117]. 

G. Gustavson, N. Demjanov,/. Prakt. Chem. 1888, 38, 201-207 in fact, the first allene to be synthesized was allene-1,3-dicarboxylic acid (glutinic acid B. S. Burton, H. v. Pech-man, Ber. Dtsch. Chem. Ces. 1887, 20,145-149), but its structure was only correctly assigned 67years later E. R. H. Jones,... 

The elimination reactions of /l-acetoxy sulfones 114 to give the donor-acceptor-substituted allenes 115 by a Julia-Lythgoe process are less conventional (Scheme 7.18) [157]. A new one-step synthesis of allene-l,3-dicarboxylates 118 from acetone derivatives 116 was developed by the use of 2-chloro-l,3-dimethylimidazolinium chloride 117 [158, 159]. This elimination of water follows also the general Scheme 7.17 if a derivative of the enol, resulting from 116, is assumed as an intermediate for an elimination step. More complex processes of starting materials 119 furnished allenyl ketones 120 in high yields [160-162]. 

Dimethyl allene-l,3-dicarboxylate 476 can react with a variety of nucleophiles with an N=C-NH2 substructure to afford monocyclic or bicyclic compounds 501. In this reaction the iminyl nitrogen first attacks the center carbon atom of the allene moiety to afford 3-amino-4-(methoxycarbonyl)-2-butenoate, in which the other nitrogen atom and the conjugated carboxylate undergo an aminolysis reaction to afford the cyclic product [226],... 

Benzylaniline can aslo react with dimethyl allene-l,3-dicarboxylate to yield ( )-/ -amino-y-methoxycarboxyl-a,/3-unsaturated enoate ( )-506 as the single stereoisomer [226, 227]. 

With HC1, allene-l,3-dicarboxylates afford (Z)-3-chloro-4-(alkyoxycarboxyl)-2-bute-noates [253],... 

Allene-l,3-dicarboxylates no are also useful dienophiles for [4+ 2]-cycloadditions. They react with 1,3-dienes to give 4-methylenecyclohexene derivatives 111. The aro-matization shown produced homophthalic derivatives 112 and 113 [96]. 

Anodic oxidation of 1,2-dicarboxylic acids as their alkali metal salts in concentrated aqueous solution gives the alkene with the loss of two molecules of carbon dioxide [125]. Succinic acid affords etltene and methylsuccinic acid ptopene [50]. Allene is obtained from itaconic acid and the isomeric methylmaleic and methyl-fumaric acids give propyne... 

Allenes react with thiourea to yield thiazine-4-ones, which are further isomerized to 4-oxothiazine-6-ylidene acetic esters (10) (Scheme 8) [(82JCS(P1)1905)]. Acetylenic esters [propiolate and (DMAD)] react with thiourea to give thiazine-4-ones 11 and 12. Substituted thioureas behave like ambident reagents with dimethylacetylene dicarboxylate (DMAD) (Scheme 9) [(69ZOR621 78JCS(P1)1428)]. Finally, the thiazines... 

As a first approach to the synthesis of nagilactone 296, a norditer-penoid isolated from Podocarpaceae, which inhibit the expansion and mitosis of plant cells, an intramolecular Diels-Alder reaction of allene 1,3-dicarboxylic acid esters was used. The cyclization of 297 afforded the 8-lactone 298, rather than the y-lactone 299 [85JCS(P1)747]. 

A number of chiral allenes, such as the following dicarboxylic acid, have been prepared and resolved. 

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