Benzaldehyde Dimethyl Acetals Research Articles

Reactivity of azoles towards benzaldehyde and its dimethylacetal. Synthesis of N,N'-diazolylphenylmethanes

Some 1,1'-diindazolylphenylmethanes have been prepared from indazoles and benzaldehyde in presence of zinc chloride as catalyst. The reaction was strongly dependent on the basic pK a 's of azoles and only few pyrazolyl derivatives could be prepared by this procedure. Extension of this method to other azoles was accomplished by using benzaldehyde dimethylacetal.

Anodic functionalisation in synthesis. Part 1. Methoxylation of methyl-substituted benzene and anisole derivatives, and the synthesis of aromatic aldehydes by anodic oxidation

The anodic oxidation in methanol of a series of alkylanisoles and hydroquinone ethers, and of p-xylene has been studied. It was established that the initial step in the product formation always involves direct anodic oxidation of the aromatic compound to the corresponding cation radical. If the electrolysis is conducted under conditions where formation of methoxyl radicals also takes place (platinum anode, supporting electrolyte NaOMe) nuclear methoxylation dominates. Substitution in the nucleus of the aromatic compound presumably occurs either by nucleophilic attack of a methoxide ion on the anodically generated cation radical or by a coupling reaction between the latter and an anodically generated methoxyl radical. If the electrolysis is conducted under conditions where formation of methoxyl radicals does not take place (carbon or platinum anode with supporting electrolyte LiBF4) side-chain oxidation of p-alkylanisoles and p-xylene, with the formation of benzyl ethers, benzaldehyde dimethyl acetals, or ortho-esters of benzoic acids becomes important. This side-chain oxidation occurs via nucleophilic attack of methanol on a benzyl cation formed by deprotonation–anodic oxidation of the initially formed cation radical. Phenol ether cation radicals without p-alkyl substituents under these conditions either dimerise or undergo nuclear methoxylation via nucleophilic attack of methanol on the cation radical.

ChemInform Abstract: SUBSTITUENT EFFECTS ON RATES AND EQUILIBRIA FOR BENZALDEHYDE ‐ BENZALDEHYDE DIMETHYL ACETAL INTERCONVERSION

Chemischer InformationsdienstVolume 6, Issue 34 Isocyclic Compounds ChemInform Abstract: SUBSTITUENT EFFECTS ON RATES AND EQUILIBRIA FOR BENZALDEHYDE - BENZALDEHYDE DIMETHYL ACETAL INTERCONVERSION T. S. DAVIS, T. S. DAVISSearch for more papers by this authorP. D. FEIL, P. D. FEILSearch for more papers by this authorD. G. KUBLER, D. G. KUBLERSearch for more papers by this authorD. J. JUN. WELLS, D. J. JUN. WELLSSearch for more papers by this author T. S. DAVIS, T. S. DAVISSearch for more papers by this authorP. D. FEIL, P. D. FEILSearch for more papers by this authorD. G. KUBLER, D. G. KUBLERSearch for more papers by this authorD. J. JUN. WELLS, D. J. JUN. WELLSSearch for more papers by this author First published: August 26, 1975 https://doi.org/10.1002/chin.197534199Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume6, Issue34August 26, 1975 RelatedInformation

Die photolytische α-spaltung von benzoinalkyläthern in sauerstoffhaltigem methanol

The primary step in the photolytical α-cleavage of benzoin alkyl ether in oxygen saturated methanol at room temperature is the formation of a benzoyl ( 1) and an α-alkoxybenzyl radical ( 2), which react via their peroxi radicals 3 und 4 to the final products yielding perbenzoic acid ( 5), alkyl benzoate ( 7), benzaldehyde ( 11), benzaldehyde dimethylacetal ( 10) and benzil to 100%. Product analysis of the final products of the photolysis of specifically deuterated benzoin methyl ethers shows that methyl benzoate, benzaldehyde and benzaldehyde dimethylacetal are formed via the α-methoxybenzyl radical ( 2) while the perbenzoic acid results from the benzoyl radical ( 1). Both the peroxi radicals 3 and 4 have an independent reaction pathway to the final products. Hydrogen abstraction of 3 and 4 from the solvent methanol give rise to hydroxy methyl radicals which yields formic acid, hydrogen peroxide, performic acid and formaldehyde via their hydroxy methyl peroxi radicals. The reaction pathway of the primary radicals is discussed.

Polar influences in radical reactions. Part VI. Hydrogen abstraction from nuclear-substituted ethylbenzenes, benzaldehyde dimethyl acetals, and diphenylmethyl methyl ethers by the trichloromethyl radical

The relative reactivities of nuclear-substituted ethylbenzenes, benzaldehyde dimethyl acetals, and diphenylmethyl methyl ethers toward the trichloromethyl radical at 80° have been determined by means of intermolecular competitive reactions. The results show a σ+ correlation by the Hammett equation with ρ-values of –0·53, –0·18, and –0·12, respectively, a decreasing polar effect consistent with the increasing reactivity of the three series.

1151. Polar influences in radical reactions. Part IV. The abstraction of benzylic hydrogen atoms from substituted benzyl methyl ethers and benzaldehyde dimethyl acetals by atomic bromine

1151. Polar influences in radical reactions. Part IV. The abstraction of benzylic hydrogen atoms from substituted benzyl methyl ethers and benzaldehyde dimethyl acetals by atomic bromine