Propiolaldehyde

The material in the first trap contains a considerable amount of water. In order to facilitate separation, the checkers saturated this mixture with sodium chloride. The upper layer, consisting of nearly pure propiolaldehyde, was combined with the contents of the second and third traps and dried over 5 g. of anhydrous magnesium sulfate. Distillation through a 12-in. vacuum-jacketed Vigreux column gave directly propiolaldehyde comparable in yield and quality with the final product described by the submitter in Note 6. 

The procedure described is that of Wille and Saffer. Propiolaldehyde has also been prepared by the oxidation of propargyl alcohol using ammonium dichromate or manganese dioxide in 10% sulfuric acid. Propiolaldehyde has also been prepared by warming the dimethyl or diethyl acetal with dilute sulfuric acid. ... 

ALKYNES VIA PHASE TRANSFER-CATALYZED DEHYDROHALOGENATION PROPIOLALDEHYDE DIETHYL ACETAL... 

Propiolaldehyde diethyl acetal has found numerous synthetic applications in the literature which may be briefly summarized. The compound has been utilized in the synthesis of unsaturated and polyunsaturated acetals and aldehydes by alkylation of metal-lated derivatives, " by Cadiot-Chodkiewicz coupling with halo acetylenes, " and by reaction with organocuprates. Syntheses of heterocyclic compounds including pyrazoles, isoxazoles, triazoles, and pyrimidines have employed this three-carbon building block. Propiolaldehyde diethyl acetal has also been put to use in the synthesis of such natural products as polyacetylenes " and steroids. ... 

Propiolaldehyde, 3-chloro-, diethyl acetal (8) 1-Propyne, 1-chloro-3,3-diethoxy- (9) (62761-29-9)... 

Dining addition of 56% aqueous acid to the aqueous 33% alcohol, using a published procedure for conversion to propiolaldehyde [1], a violent explosion was attributed to lack of adequate cooling [2], This attribution is disputed, and contamination, possibly with a heavy metal ion, is postulated [3], The published procedure is rated not hazardous. 

Propargyl alcohol, 36, 67 Propiolaldehyde, 36, 66 Propionic acid, /3,/3 -thiodi-, dimethyl ester, 30, 65... 

Phenyl, phenylethynyliodonium perchlorate, 3635 Poly(2,4-hexadiyne-l,6-ylene carbonate), 2669 Potassium acetylene-1,2-dioxide, 4934 Potassium ethynediolate, 0990 Potassium hydrogen acetylenedicarboxylate, 1382 Propiolaldehyde, 1085... 

PHENYLPROPARGYL ALDEHYDE DIETHYL ACETAL (Propiolaldehyde, phenyl-, diethyl acetal)... 

With monosubstituted acetylenes, such as phenylacetylene (94) and propiolaldehyde diethyl acetal (95), the orientation of phenyl azide is determined both by electronic and steric effects.307 08... 

Propyl(thioisonicotinamide), see 2-Propylpyridine-4-carbothioamide, 3157b Propynal, see Propiolaldehyde, 1082... 

Aldehydes containing the grouping —C sC- CHO do not undergo dis-mutation when treated with alkali but are cleaved readily to yield the corresponding acetylene and formic add. Propiolaldehyde and phenyl-and methyl-propiolaldehydes are cleaved smoothly in the following way.68... 

Similarly, ester-activated methylene groups react with propiolaldehydes (Scheme 139) <2004TL9197> and 1,2-allenic ketones (Scheme 140) <20020L505, 2003JOC8996> to afford 2//-pyran-2-ones. 

DeMaster EG, Summer HW, Kaplan E, et al. 1982. Partying-induced hepatotoxicity Possible mediation by the reactive metabolite, propiolaldehyde. Toxicol Appl Pharmacol 65 390-401. 

Aminocyclohex-2-en-l-one reacts with propiolaldehyde to yield 5-oxo-5,6,7,8-tetra-hydroquinoline (303) (equation 125)152. 

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