Neue RingtransformationN-unsubstituierter 1,2,3-Triazole: Umwandlung vonN-(1,2,3-Triazolyl)-hydrazonoylbromiden in funktionalisierte 1,2,4-Triazole

Rearrangement of substituted azido-1,2,3-triazolides to (α-diazoalkyl)tetrazolides

“…To explore the electronic effects of the substituents R we calculated the atomic charges for 4Ј and the corresponding transition state TS 1 . The results summarised in Table 4 show that N(1) is the ring atom with the largest negative charge and, in agreement with the experimental results obtained with 4Јa-g, is only slightly affected by the nature of the substituent R. Major effects are observable for N(3) and C (5). The electron acceptors R = CN, CO 2 Me and COC 6 H 4 Me-p as well as the phenyl moiety diminish the atomic charge at these positions.…”

“…2 We have shown that in this case the (diazomethyl)tetrazolide ion (C; X = CH) was formed as the final product, 3 apparently by a process related to the degenerate rearrangement of azidotetrazolide [(A; X = Y = Z = N)→(C; X = N)]. 4 Since ligands on the 1,2,3-triazole ring carbon atom are expected to affect the ease of this conversion-a rare type of 1,2,3-triazole ring transformation 5 we launched a study of its scope.…”