Multicomponent reactions of amino alcohols with CH2O and dithiols in the synthesis of 1,3,5-dithiazepanes and macroheterocycles

Samarium(III) nitrate-catalyzed one-pot synthesis of 42-membered N,S,O-containing cyclophanes

“…In previous studies of non-catalyzed heterocyclization of aminophenols, 45 and primary hydroxylamines 14 with СН 2 О and SH-acids, we found that multicomponent cyclocondensation affords cyclophanes as mixtures with by-products. For the more selective synthesis of heteroatom cyclophanes, we performed catalytic heterocyclization of N,N-bis(methoxymethyl)-N-arylamines with 4,4′-dimercaptodiphenyl oxides.…”

“…[1][2][3][4][5][6][7] A considerable drawback of this method is the formation of by-products arising from linear polycondensation or simultaneous [n+n]-cyclocondensation of the initial α,ω-bifunctional compounds. [8][9][10][11][12][13][14] The formation of by-products is minimised, as a rule, by using high dilution, 11,15,16 templates, [17][18][19][20][21][22] and catalytic reactions. [23][24][25][26][27] Cyclophanes containing benzene rings in the molecule have rigid cyclic skeletons, which is important for their complexation of metal ions 5 and organic molecules.…”

Efficient catalytic synthesis of N-cycloalkyl-1,5,3-dithiazepanes

“…Three-component condensation of primary amines with formaldehyde and ethane-1,2-dithiol provides a well known method of synthesis of N-substituted 1,5,3-dithiazepanes [1,2]. However, the catalytic recyclization of 1-oxa-3,6-dithiacycloheptane with primary amines allows selective preparation of N-aryl- [3,4] and N-alkyl-1,5,3-dithiazepanes [5,6] which are potential bactericidal, antimicrobial, and fungicidal agents [7,8].…”

“…The reaction of cyclopropanamine with an equimolar amount of 1-oxa-3,6-dithiacycloheptane (1) in a mixture of ethanol with chloroform at room temperature in the absence of a catalyst in 3 h afforded 3-cyclopropyl-1,5,3-dithiazepane (2) in no more than 40% yield. To improve the yield of 2, the reaction of 1 with cyclopropanamine was carried out in the presence of transition (Cu, Pd, Co, Ni, Zr, Ti) and rare earth metal salts (La, Sm, Eu, Yb) which were used previously to catalyze heterocyclization reactions [3][4][5][6].…”

“…To improve the yield of 2, the reaction of 1 with cyclopropanamine was carried out in the presence of transition (Cu, Pd, Co, Ni, Zr, Ti) and rare earth metal salts (La, Sm, Eu, Yb) which were used previously to catalyze heterocyclization reactions [3][4][5][6]. The most active were catalysts based on rare earth metals, and the yield of 3-cyclopropyl-1,5,3-dithiazepane (2) Under the optimal conditions (5 mol % of SmCl 3 · 6 H 2 O, EtOH-CHCl 3 , 20°C, 3 h), cycloalkylamines reacted with 1-oxa-3,6-dithiacycloheptane (1) yielding 50-87% of N-cycloalkyl-1,5,3-dithiazepanes 2-4 and 8-11 (Scheme 1). As the ring size of the initial cycloalkylamine increased, the yield of 1,5,3-dithiazepanes 2-4, 8, and 9 increased from 74 to 86%.…”