Synthesis of new thiophene, furan and pyridine substituted 1,2,4,5-oxadiazaboroles

Twenty-two new 3,4,5-trisubstituted 1,2,4,5-oxadiazaboroles were prepared by the cyclocondensation reaction of N-substituted thiophene, furan and pyridine carboxamidoximes with phenylboronic acid in refluxing toluene in good yields. The structures of the new oxadiazaboroles were elucidated by means of spectral measurements (IR, 1H, 13C, 11B NMR, MS, X-ray) and physical data (melting points, elemental compositions by HRMS).

Graphical abstractTwenty-two new 3,4,5-trisubstituted 1,2,4,5-oxadiazaboroles were prepared by the cyclocondensation reaction of N-substituted thiophene, furan and pyridine carboxamidoximes with phenylboronic acid in refluxing toluene in good yields.The structures of the new oxadiazaboroles were elucidated by means of spectral measurements (IR, 1H, 13C, 11B NMR, MS, X-ray) and physical data (melting points, elemental compositions by HRMS).Figure optionsDownload full-size imageDownload as PowerPoint slide