R. F. Karimova

Synthesis and oxidation of (4-hydroxy-3,5-di- tert -butylphenyl)-methanebis[diethyl(diphenyl)phosphine oxides]

The phosphorylated sterically hindered phenols and methylenequinones are potential inhibitors of oxidation of organic materials like polymers, petrochemical products, and biological systems [1–2]. In extension of studying the reaction of geminal polyhalides with aprotic nucleophilic reagents [3–5] we studied the reaction of 4-hydroxy-3,5-di-tert-butylbenzal chloride I with diethyl and diphenyl chlorophosphines. The reaction of dichloride I with diethyl chlorophosphine was found to proceed at keeping the hexane solution of reagents taken in the ratio 1:2 at room temperature for 24 h. The reaction of dichloride I with diphenyl chlorophosphine requires the heating of the reagents mixture at 100–110°С for 3 h. Adducts III form in high yields as colorless hygroscopic viscous products, weakly fuming in the air. According to the Р NMR spectra, compounds IIIa (δP 69.36 ppm) and IIIb (δP 71.02 ppm) have phosphonium structure in keeping with the literature data [6, 7]. The treatment of adducts IIIa and IIIb with anhydrous ethanol followed by evaporating of the solvents in a vacuum gives the corresponding bisphosphine oxides IV. DOI: 10.1134/S1070363210030278

Reactions of P(III) chlorides with aldehydes: I. Synthesis of primary intermediates of the reactions of aliphatic aldehydes with P(III) chlorides possessing electrophilic properties

An approach to investigation of reactions of electrophilic P(III) chlorides with aliphatic aldehydes is developed. Its essence is the removal of HCl impurity from chloride and catalytic blocking of electrophilic center of the carbonyl group. For these purposes nitrogen-containing organic bases and alkyl vinyl ethers are used. Three types of primary intermediates with the nearest P(III) environment POCl2, O2PCl, and O3P are synthesized. It is established that the stability of intermediates increases with the growing acceptor properties of substituents at P(III) and donor properties of the aldehyde fragment.

Synthesis of 4-(dibromomethyl)benzenecarbaldehyde and its reactions with N- and O-nucleophiles

Abstract4-(Dibromomethyl)benzenecarbaldehyde was first synthesized and its preparation method jointly with terephthalic aldehyde was developed. Its reactions with O- and N-nucleophiles were studied: the reaction of this aldehyde with trialkyl orthoformates results in the formation of acetals while reacting with primary amines it forms imines, including those containing an additional acetal group.

Synthesis of (4-hydroxy-3,5-di-tert-butylphenyl)-chloromethanediphenylphosphine oxide and its reactions with aprotic nucleophilic reagents

Reaction of (4-hydroxy-3,5-di-tert-butylphenyl)chloromethanediphenylchlorophosphonium chloride with trimethyl orthoformate affords (4-hydroxy-3,5-di-tert-butylphenyl)chloromethanediphenylphosphine oxide. The latter undergoes dehydrochlorination under the action of trimethyl orthoformate and O-methyl diethylphosphinate, and with diphenylchloro- and triphenyl phosphines it gives the corresponding phosphonium salts.

Synthesis and properties of [(4-Hydroxy-3,5-di-tert-butylphenyl)-chloromethanediphenylphosphine oxide

Received March 23, 2012 LETTERS TO THE EDITOR ISSN 1070-3632, Russian Journal of General Chemistry, 2012, Vol. 82, No. 9, pp. 1587–1589.

Synthesis and Properties of Some Sulfur-Containing Derivatives of Phosphorylated Sterically Hindered Phenols

The addition of thioacetic acid to 2,6-di-tert-butyl-4-(phosphorylmethylidene)cyclohexa-2,5-dien-1-ones has been accomplished for the first time. The resulting adduct is readily hydrolyzed with hydrazine hydrate to give 2,6-di-tert-butyl-4-[phosphoryl(sulfanyl)methyl]phenols, and the latter reacted with the initial quinomethanes, yielding 4,4′-[sulfanediylbis(phosphorylmethylene)]bis(2,6-di-tert-butylphenols).

Reactions of phosphorylated 2,6-di- tert -butyl-4-methylidenecyclohexa-2,5-dien-1-ones with aliphatic, aromatic, and heteroaromatic thiols

The addition of alkanethiols, benzenethiol, and hetarenethiols to phosphorylated quinomethanes afforded P,S- and N,P,S-containing polyfunctional organic compounds as potential bactericidal agents.

Reaction of P(III) chlorides with aldehydes: II. Reaction of primary intermediates with aprotic nucleophiles: Ethylene oxide, acetals, trialkyl orthoformates, and trialkyl phosphites

Structure of primary intermediates of the reaction of P(III) chlorides with aliphatic aldehydes was confirmed by their reactions with such aprotic reagents like ethylene oxide, trialkyl phosphites, acetals, and trialkyl orthoformates. Principle difference in the reactions of these nucleophiles with intermediates containing active chlorine atom at P(III) and those not containing was established. The former as well as all the other P(III) chlorides react directly with nucleophiles, while the latter slowly decompose into aldehyde and P(III) chloride, and the latter reacts with the nucleophile.

On the reaction of 4-chloromethylene-2,6-di-tert-buthylcyclohexa- 2,5-dien-1-one with P(III) acids esters

Proceeding with investigations on reactions of organic halides with aprotic reagents [1, 2], we pioneered in studying reactions of 4-chloromethylene2,6-di-tert-butylcyclohexa-2,6-dien-1-one I (chloromethylenequinone) with P(III) acids esters, such as triethyl phosphite IIа and ethyl diphenylphosphinite IIb. Phosphorylated ylides VII were established to be the main products of the reaction of chloromethylenequinone I with esters II in a 1:2 ratio. We suppose that ylide VII is formed by the following two-stage scheme: DOI: 10.1134/S1070363209010307

Synthesis of Dialkyl (1-Hydroxy-2,2-dimethyl- 3-(dialkylamino)propyl)phosphonates

We found that compounds III can be prepared by reaction of dialkyl hydrogen phosphites I with 3-(dialkylamino)-substituted aldehydes II. Addition of ethanolic sodium ethylate or a little sodium to a mixture of compounds I and II gives rise to an exothermic reaction. After neutralization of the reaction mixture with acetic acid and evaporation of volatile substances in a high vacuum, compounds III were identified as crude materials, since they decomposed on attempted vacuum distillation. Compounds III can also be obtained by heating a mixture of compounds I and II at 80oC. Under these conditions, nucleophilic catalysis takes place due to the presence in the starting aldehydes of a tertiary amino group.