释义 |
malonic, a. Chem.|məˈlɒnɪk| [a. F. malonique (Dessaignes 1858, in Comptes Rendus XLVII. 76), arbitrarily altered from malique mal-ic.] In malonic acid: an acid obtained by the oxidation of malic acid; malonic ester, the diethyl ester, CH2(COOC2H5)2, of malonic acid, which is a liquid widely used in synthesis, as of carboxylic acids RR′C(COOH)2 or RR′CHCOOH by alkylation with alkyl halides (malonic ester synthesis).
1859Watts tr. Gmelin's Handbk. Chem. XIII. 560. 1881 Chem. News 28 Jan. 47/1 (heading) Syntheses by means of malonic ester. 1888I. Remsen Org. Chem. 204 Treated with an alkali, barbituric acid breaks up into malonic acid and urea. 1906J. J. Sudborough Bernthsen's Text-bk. Org. Chem. (rev. ed.) x. 238 This so-called ‘malonic ester’ synthesis is an important method for the preparation of higher dibasic acids. 1968R. O. C. Norman Princ. Org. Synthesis x. 330 The use of malonic ester considerably increases the versatility of this general method [of amino-acid synthesis]. 1971N. Allinger et al. Org. Chem. xxiv. 665 In the malonic ester synthesis, diethyl malonate is converted by sodium ethoxide into its sodium salt, which is then allowed to react with an alkyl halide. Hence ˈmalonyl, the radical {b1}CO·CH2·CO{b1} derived from malonic acid by removal of the two hydroxyl groups.
1889G. M'Gowan tr. Bernthsen's Text-bk. Org. Chem. 282 Barbituric acid, malonyl urea, C4H4N2O3, is a dibasic acid. 1931Jrnl. Chem. Soc. 273 The Friedel-Crafts reaction has now been extended to the coupling of malonyl chloride..with methyl ethers of resorcinol. 1970R. W. McGilvery Biochem. xvi. 317 The butyryl group can be displaced onto the neighboring cysteinyl group by an incoming malonyl group. 1971Nomencl. Org. Chem. (I.U.P.A.C.) (ed. 2) C. 313 Malonyl (preferred to propanedioyl) {b1}CO·CH2·CO{b1}. |