Silica‐supported ICl as a novel heterogeneous system for the rapid oxidation of urazoles to triazolinediones

Synthesis and Structure of bis(cyclohexylmethyl) 3,6-bis(4-chlorophenyl)-1,2,4,5-tetrazine-1,2-dicarboxylate

“…[1][2][3][4][5][6][7][8][9][10][11] Although various reagents are capable of effecting the oxidation of urazoles, this transformation remains difficult because the initial compounds are very sensitive to the oxidant, and the preparation and purification of these compounds are problematical due to their unusual reactivity and sensitivity to reaction conditions. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Some new oxidising reagents have been prepared, and several techniques have been used. Most of them suffer at least from one of the following disadvantages: (1) high costs of preparations, (2) long reaction times, (3) hygroscopicity, (4) no selectivity, (5) photosensitivity, (6) dangerous procedures for their preparation, and (7) tedious work-up procedures.…”

“…Most of them suffer at least from one of the following disadvantages: (1) high costs of preparations, (2) long reaction times, (3) hygroscopicity, (4) no selectivity, (5) photosensitivity, (6) dangerous procedures for their preparation, and (7) tedious work-up procedures. [21][22][23][24][25][26][27][28][29][30][31][32] In continuation of our previous works, on oxidation and synthesis of heterocyclic compounds, [33][34][35][36][37][38][39] we now introduce an efficient, mild and rapid method for the oxidation of urazoles to their corresponding 4-substituted-1,2,4-triazole-3,5-diones (TADs), by using benzyltriphenylphosphonium nitrate (I, BTPPN) as a mild and novel oxidising reagent which is readily prepared by reaction of an aqueous solution of benzyltriphenylphosphonium chloride with NaNO 3 solution at room temperature (Scheme 1).…”

New Conditions for the Effective Synthesis of Tri and Tetrasubstituted Imidazoles Catalysed by Recyclable Indium (III) Triflate and Magnesium Sulfate Heptahydrate

“…In connection with our studies on new catalysed organic reactions, [3][4][5] indium (III) trifluoromethanesulfonate and magnesium sulfate heptahydrate were found to be powerful, safe and recyclable catalysts for the one-pot condensation reaction to tri/tetrasubstituted imidazole derivatives. Especially, MgSO 4 .7H 2 O is quite environmentally safe and has medicinal properties when used both externally and internally.…”

Oxidation of Urazoles to their Corresponding Triazolinediones using Benzyltriphenylphosphonium Nitrate

“…[1][2][3][4][5][6][7][8][9][10][11] Although various reagents are capable of effecting the oxidation of urazoles, this transformation remains difficult because the initial compounds are very sensitive to the oxidant, and the preparation and purification of these compounds are problematical due to their unusual reactivity and sensitivity to reaction conditions. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Some new oxidising reagents have been prepared, and several techniques have been used. Most of them suffer at least from one of the following disadvantages: (1) high costs of preparations, (2) long reaction times, (3) hygroscopicity, (4) no selectivity, (5) photosensitivity, (6) dangerous procedures for their preparation, and (7) tedious work-up procedures.…”

“…Most of them suffer at least from one of the following disadvantages: (1) high costs of preparations, (2) long reaction times, (3) hygroscopicity, (4) no selectivity, (5) photosensitivity, (6) dangerous procedures for their preparation, and (7) tedious work-up procedures. [21][22][23][24][25][26][27][28][29][30][31][32] In continuation of our previous works, on oxidation and synthesis of heterocyclic compounds, [33][34][35][36][37][38][39] we now introduce an efficient, mild and rapid method for the oxidation of urazoles to their corresponding 4-substituted-1,2,4-triazole-3,5-diones (TADs), by using benzyltriphenylphosphonium nitrate (I, BTPPN) as a mild and novel oxidising reagent which is readily prepared by reaction of an aqueous solution of benzyltriphenylphosphonium chloride with NaNO 3 solution at room temperature (Scheme 1).…”