aldoln.
/ˈaldɒl/, U.S. /ˈælˌdɔl/, /ˈælˌdɑl/ Chemistry.
1. A viscous liquid compound produced from acetaldehyde (ethanal) by a dimerization reaction in dilute alkali or acid.Systematic name: 3-hydroxybutanal; CH3CH(OH)CH2CHO.
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the world > matter > chemistry > organic chemistry > aldehydes or alkanals > [noun] > aldols
aldol1872
1872 Jrnl. Chem. Soc. 25 808 This, when purified by rectification under a pressure of 20 mm., passes over as a colourless liquid to which the author [sc. Adolphe Wurtz] has given the name of aldol.
1907 H. D. Haskins & J. L. R. MacLeod Org. Chem. 104 Aldehyde molecules can be made to fuse together, forming a ‘condensation’ product, aldol.
1981 P. Sykes Guidebk. to Mechanism in Org. Chem. (ed. 5) viii. 220 Thus with ethanal, CH3CHO, the product is 3-hydroxybutanal—aldol itself.
2001 A. Clayden et al. Org. Chem. xxvii. 689 The product [sc. 3-hydroxybutanal] is an aldehyde with a hydroxy (ol) group whose trivial name is aldol.
2. Any analogous compound with neighbouring alcohol and aldehyde (or, more widely, carbonyl) groups; spec. a β-hydroxy aldehyde or ketone.
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1891 E. F. Smith tr. V. von Richter Chem. Carbon Compounds (2nd U.S. ed.) 962 The first step in the reaction consists in two molecules combining to unsaturated aldehydes, CHO.CR:CH.CH2R, or condensing to aldols corresponding to them.
1934 C. C. Steele Introd. Plant Biochem. iii. vii. 61 Acetaldehyde and higher members of the aliphatic homologous series, CnH2n +1CHO, condense together in the presence of aqueous potassium carbonate to give compounds which contain both an aldehydic and an alcoholic group, viz. aldols.
1983 McGraw-Hill Encycl. Chem. 20/2 Aldols are readily dehydrated to form unsaturated aldehydes.
2006 S. P. Robins in M. J. Seibel et al. Dynamics Bone & Cartilage Metabolism (ed. 2) ii. 46/2 Hydroxyallysine does not form intramolecular aldols and no corresponding products from this pathway have been detected.
Compounds
aldol condensation n. [after German Aldolcondensation (1885 in the passage translated in quot. 1886; now Aldolkondensation)] a reaction between two aldehyde or two ketone molecules (or an aldehyde and a ketone) to yield a single molecule with one hydroxyl and one carbonyl group (exemplified by the conversion of acetaldehyde to aldol), this product typically losing a water molecule readily to form an unsaturated aldehyde or ketone.
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the world > matter > chemistry > chemical reactions or processes > [noun] > chemical reactions (general) > specific
hydrolysis1880
aldol condensation1886
aldol reaction1888
aldolization1898
base exchange1912
acidolysis1930
1886 E. F. Smith tr. V. von Richter Chem. Carbon Compounds 152 The aldehydes condense readily, i.e., two molecules unite by means of two carbon atoms and water may or may not separate (aldehyde and aldol condensation [Ger. Aldehyd- und Aldolcondensation]).
1968 A. White et al. Princ. Biochem. (ed. 4) xviii. 397 This enzyme can catalyze an aldol condensation between dihydroxyacetone phosphate and a wide variety of aldehydes.
2006 J. M. Hornback Org. Chem. (Internat. Student ed.) xx. 896 The Michael reaction in combination with an aldol condensation provides a useful method for the construction of six-membered rings.
aldol reaction n. = aldol condensation n.
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the world > matter > chemistry > chemical reactions or processes > [noun] > chemical reactions (general) > specific
hydrolysis1880
aldol condensation1886
aldol reaction1888
aldolization1898
base exchange1912
acidolysis1930
1888 Jrnl. Chem. Soc. 54 477 Perkin's reaction is strictly analogous to the aldol reaction of Wurtz.
1936 W. J. Hickinbottom Reactions Org. Compounds iv. 139 The simplest type of reaction is that exemplified by the aldol reaction.
2010 Tetrahedron 66 2635/2 In the key step, the C2-C3 bond was created by an aldol reaction.
This entry has been updated (OED Third Edition, September 2012; most recently modified version published online December 2021).
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