An unprecedentedly simple method of synthesis of aryl azides and 3-hydroxytriazenes

Abstract

Fischer's approach towards the synthesis of aryl azides and triazinoles from diazonium salts and hydroxylammonium chloride (phenylhydraxylamine) was reinvestigated and optimized.

Synthesis of 1‐(3‐(1‐substituted‐1,2,3‐triazol‐4‐yl)‐1,2,4‐triazol‐5‐yl)‐tetrazoles by Sequential Assembly of Azole Fragments

“…Halogen‐derived phenyl azide 12 f has a melting point close to room temperature and should be filtered and washed with ice‐cold water. Interestingly enough, the color of 4‐bromophenyl azide 12 f is reported as “green”, “yellow” and “brown” in different publications, [44,45] but we established that freshly obtained it is a white compound which should be stored in cold: even at room temperature it quickly changes to green and then to brown.…”

Copper(I) Chloride Mediated Amination of Halobenzenes via Azides: Scope, Mechanistic Aspects, and C–C Cleavage Reactions

“…This component does not bear any amine protons, but a singlet at 11.7 ppm is present, and this chemical shift may fit an OH-proton; however, the 13 C NMR chemical shift of the ipso-C does not agree with the reported one for a comparable orthoalcohol, 46 and the alcohol was not detected by MS. HRMS (APCI) shows molecular ions with masses 303 and 275 Da corresponding to fragments of 4e and possibly 4eb as both are of the same mass. Furthermore, the 13 C NMR chemical shift of the ipso-C of the triazene group is in agreement with the reports of similar triazene compounds, 47 and the 1 H NMR resonance at 11.7 ppm fits as well to a triazene H, with resolved 3 J H−C correlations in the HMBC spectrum for the C(2) and C(6) ring carbons (Supporting Information, pages S47 and S48). Based on these facts, we assign the structure tentatively to triazene 4eb.…”

Synthesis and immunopharmacological evaluation of novel TLR7 agonistic triazole tethered imidazoquinolines

“…Compound 5 (500 mg, 1.8 mmol) was dissolved in MeOH : dichloromethane : chloroform (0.1 : 1 : 1) containing peracetic acid (32% active oxygen, 776 mg, 4.5 mmol). The solution was heated at 45–50 °C (internal temperature) for 2 h, and the reaction mixture was concentrated using rotary evaporator 14 and the residue was purified using column chromatography (8% MeOH/CH 2 Cl 2 ), to obtain the compound 6 (438 mg, 83%). 8 1 H NMR (400 MHz, CDCl 3 ) δ 9.07–9.02 (m, 2H), 8.12–8.07 (m, 1H), 7.78–7.72 (m, 2H), 4.33 (d, J = 7.6 Hz, 2H), 3.18 (t, J = 7.5 Hz, 2H), 2.90 (ddd, J = 8.4, 6.9, 2.6 Hz, 2H), 2.41–4.31 (m, 1H), 2.03 (t, J = 2.6 Hz, 1H), 1.05 (d, J = 6.7 Hz, 6H).…”