A. S. Gazizov

Interaction of 2-Naphthol with γ-Ureidoacetals. A New Method for the Synthesis of 2-Arylpyrrolidines

We report a new, single-stage method for the synthesis of 2-arylpyrrolidines, based on an acid-catalyzed reaction of 2-naphthol with γ-ureidoacetals, enabling the preparation of the target compounds under mild conditions, while avoiding costly reagents and catalysts.

Acid-Catalyzed Reaction of (4,4-Diethoxybutyl)ureas with Phenols as a Novel Approach to the Synthesis of α-Arylpyrrolidines

Abstract 1-(4,4-Diethoxybutyl)-3-alkylureas undergo intramolecular cyclization in the presence of trifluoroacetic acid and various phenols, leading to the new N-alkyl-2-arylpyrrolidine-1-carboxamides with moderate to excellent yields. It was found that these compounds undergo spontaneous solid-phase epimerization at room temperature. Advantages of the proposed approach are mild reaction conditions and no need for expensive reagents or catalysts. GRAPHICAL ABSTRACT

Reaction of resorcinol and its derivatives with urea acetals

Reaction of 2-methylresorcinol and pyrogallol with urea acetals of various structures was studied. Depending on the structure of the acetal used, reaction was established to result in eiter calix[4]resorcinols containing urea fragment or in imidazolidin-2-one derivatives.

Synthesis of novel 2-arylpyrrolidines by the reaction of 1-(4,4-diethoxybutyl)urea with resorcinols

Reaction of 1-(4,4-diethoxybutyl)urea with resorcinol, 2-methylresorcinol and pyrogallol in chloroform in the presence of trifluoroacetic acid affords new 2,2′-(1,3-phenylene)-bis(pyrrolidine-1-carboxamides).

Reaction of N-(2,2-Dimethoxyethyl)-N-methylamine and its N-functional derivatives with resorcinol and 2-methylresorcinol. Calix[4]resorcinols functionalized on the lower rim

Reactions of N-(2,2-Dimethoxyethyl)-N-methylamine and its derivatives with resorcinol and 2-methylresorcinol were studied. Calix[4]resorcinols having aminometyl groups of various structure on the lower rim were obtained.

Synthesis and properties of N-[2,2-bis(2,4-dihydroxyaryl)ethyl]-N-methylamines and their hydrohalides

Condensation of one molecule of α-methylaminoacetaldehyde dimethyl acetal with two molecules of resorcinol or methylresorcinol in hydrohalogen acid solutions led to substituted N-(2,2-diarylethyl)-N-methylamine hydrohalides. Reactions of the corresponding amines with acetic anhydride, mono-and diisocyanates, and formaldehyde were studied. Conditions for formation of calixarene from resorcinol and α-methylaminoacetaldehyde dimethyl acetal were invented.

Facile synthesis of 2-(2-arylpyrrolidin-1-yl)pyrimidines via acid-catalyzed reaction of N-(4,4-diethoxybutyl)pyrimidin-2-amine with phenols

N-(4,4-diethoxybutyl)pyrimidin-2-amine undergoes acid-catalyzed intramolecular cyclisation in the presence of phenols leading to the formation of 2-(2-arylpyrrolidin-1-yl)pyrimidine derivatives. Target compounds were obtained with moderate to good yields by operationally simple one-step procedure.Graphical abstract

Reaction of α-aminoacetals with 2-methylresorcinol

The main method of synthesis of calix[4-resorcinols is the condensation of resorcinol and its derivatives with aliphatic or aromatic aldehydes [1–3]. We have recently extended synthetic opportunities of this method by involvement into the reaction with resorcinol of phosphorylated acetals to obtain calix[4] resorcinols with phosphorylalkyl substituents at the lower rim of the molecule [4]. A special attention should be paid to their aminoalkyl analogs that can serve as primary compounds (due to involvement of amino groups) in the syntheses of new cavitands, container compounds, and nanotubes. For the synthesis of the calixarenes of this type we studied reaction of aminoacetaldehyde diethylacetal (Ia) and dimethylaminoacetaldehyde diethylacetal (Ib) with 2-methylresorcinol. We found that synthetic result of this reaction depends considerably on the reaction conditions. The process carried out in dioxane in the presence of trifluoromethanesulfonic acid leads to formation of calix[4]resorcinols IIIa and IIIb as the final products. DOI: 10.1134/S1070363209090199

Reaction of 1-(2,2-dimethoxyethyl)-1-methyl-3-phenylurea with pyrogallol

Reaction of formaldehyde diethylacetal with resorcinol in acid medium leads to formation of a cyclic tetramer, calix[4]resorcinol [1]. In the reactions of phosphorylated acetals with resorcinol calixarenes were formed containing phosphorylalkyl or thiophosphorylalkyl groups at the bottom rim of the molecule [2–4]. The condensation of resorcinol with αmethylaminoacetic aldehyde dimethylacetal (I) in aqueous solutions of hydrochloric acid led to the formation of hydrochlorides of substituted polyphenolic products originating from two resorcinol and one aminoacetal molecules [5].

Reaction of N-cyclohexyl-2-(2-hydroxynaphthalen-1-yl)pyrrolidine-1-carboxamide with resorcinol and its derivatives and synthesis of polyphenols

An acid-catalyzed pyrrolidine ring opening in 2-(2-hydroxynaphthalen-1-yl)pyrrolidine-1-carboxamides in the presence of resorcinols furnished new calix[4]resorcinols or 1,1-diarylbutanes modified with urea fragments. The process follows the retro-Mannich reaction mechanism, with the 2-naphthol fragment playing the role of the leaving group.