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The acetoacetic ester condensation consist in the reaction in the presence of certain bases, of an ester having hydrogen on the alpha carbon atom with a second molecule of the same ester or with another ester to form a beta-ketoester. The bases capable of effecting such reactions include sodium alkoxides, triphenylmethylsodium, sodium amide, certain Grignard reagents. Metallic sodium effects certain condensations, the sodium, alkoxide which is formed in the reaction mixture probably serves as the active condensing agents. The classical example of the acetoacetic ester reaction is the formation of acetoacetic ester itself by the condensation of ethyl acetate by means of sodium ethoxide. Keywords: acetoacetic ester; condensation; side reactions; Dieckmann reaction; acylation; esters; acid chlorides; sodium; experimental conditions

o-Methylbenzyl alcohol intermediate: o-Methylbenzyl acetate intermediate: 2-methylbenzylethyldimethylammonium bromide product: o-Methylbenzyl alcohol intermediate: 2,3-dimethylbenzyl acetate product: 2,3-dimethylbenzyl alcohol Keywords: alkylation, N-alkylation; hydrolysis, esters and lactones; replacement reactions, ammonium by oxygen; replacement reactions, miscellaneous; (2-methylbenzyl)ethyldimethylammonium bromide, preparation of

β-Diketones from methyl alkyl ketones: 3-n-butyl-2,4-pentanedione reactant: 28.6 g. (0.251 mole) of 2-heptanone reactant: 51.0 g. (0.500 mole) of acetic anhydride solvent: 100-ml. portions of petroleum ether product: 3-n-butyl-2,4-pentanedione product: 3-methyl-2,4-pentanedione product: 3-ethyl-2,4-pentanedione product: 3-phenyl-2,4-pentanedione product: 3,3-dimethyl-2,4-pentanedione product: 2-acetylcyclohexanone product: 2-acetylcyclopentanone product: 3-methyl-2,4-hexanedione product: 1,3-diphenyl-2,4-pentanedione product: benzoylacetone Keywords: acylation; boron trifluoride-acetic acid complex, 1:1, preparation

2-n-Butyl-2-methylcyclohexanone reactant: 123 g. (1.10 moles) of 2-methylcyclohexanone reactant: 81.4 g. (1.10 moles) of ethyl formate intermediate: Sodio-2-formyl-6-methylcyclohexanone reactant: 28.2 g. (0.21 mole) of n-butyl bromide product: 2-n-butyl-2-methylcyclohexanone byproduct: 2-formyl-6-n-butyl-6-methylcyclohexanone product: 2,2-Dimethylcyclohexanone product: 2-benzyl-2-methylcyclohexanone Keywords: acylation; alkylation, C-alkylation; cleavage, ketonic; ethyl formate; potassium amide, preparation of; ammonia; potassium

Ethyl β-phenyl-β-hydroxypropionate product: Ethyl α,α-dimethyl-β-phenyl-β-hydroxypropionate product: Ethyl β-phenyl-β-hydroxypropionate Keywords: Grignard and related reactions; benzaldehyde; ethyl bromoacetate; zinc; ethyl bromoacetate, lachrymator

Esterification of hindered alcohols: tert-butyl p-toluate reactant: 5.42 g. (0.0351 mole) of p-toluoyl chloride product: tert-butyl p-toluate product: tert-butyl phenylacetate product: triethylcarbinol ester of p-toluic acid product: 2,2-diphenylethanol ester of benzoic acid product: C6H5CH2CO2C(CH3)3 product: C6H5CO2CH2CH(C6H5)2 product: C6H5CO2C(CH3)3 product: C6H5CO2CCH3(C2H5)2 product: C6H5CO2C(C2H5)3 product: C6H5CO2CH2(t-C4H9) product: (CH3)3CCO2C(CH3)3 product: (CH3)3CCO2C(C2H5) product: (i-C3H7)2CHCO2C(C2H5)3 product: C6H5CHCHCO2C(CH3)3 product: (tC4H9)CH2CO2C(C2H5)3 product: C6H5CH2CH2CO2C(CH3)3 product: (tC4H9)2CHCO2C(C2H5)3 Keywords: esterification, unsubstituted monobasic acids; tert-butyl alcohol; diethyl ether; lithium tert-butoxide, preparation of; p-toluoyl chloride, preparation of

α,α,β-Triphenylpropionitrile reactant: 30.5 g. (0.24 mole) of benzyl chloride product: α,α,β-triphenylpropionitrile Keywords: alkylation, C-alkylation; potassium amide, preparation of; ammonia; potassium

The 1,4-dianions of acetophenone, para-substituted acetophenones, deoxybenzoin and dibenzyl ketone phenylhydrazone were prepared by treatment of the respective phenylhydrazone with two molecular equivalents of n-butyllithium in tetrahydrofuran-hexane at 0° and condensed with a variety of aromatic esters, followed by acid cyclization to give the substituted pyrazole in good yield. The synthesis procedure appears to be a convenient and unequivocal method for preparing a particular pyrazole isomer without interfering side reactions. The 1,4-dianion of N,N-diphenylsemicarbazone was also prepared, and the condensation-cyclization gave the pyrazole in somewhat lower yield.

Aroylations at the methyl groups of N-acetylbenzamide and p-benzoylaminoacetophenone, and at a methylene position of succinimide with appropriate aromatic esters were effected by means of sodium hydride in refluxing monoglyme. Benzoylation at the amide group of α-benzoylacetamide and salicylamide were accomplished similarly. The yields of β-keto imides from these C- and N-aroylations by sodium hydride, with which intermediate dianions were evidently not formed, were generally much better than those obtained through dianions produced by means of an alkali amide in liquid ammonia. The synthetic utility of the sodium hydride method is discussed.