TY - JOUR
T1 - Benzazole-N-BH3 adducts. Reductive transposition of 2-benzimidazole, 2-benzothiazole, and 2-benzoxazole N-BH3 adducts to 1,3,2-benzimidazaborole, 1,3,2-benzoxaborole, and 1,3,2-benzothiazaborole
AU - Padilla-Martínez, Itzia I.
AU - Andrade-López, Noemí
AU - Gama-Goicochea, Miguel
AU - Aguilar-Cruz, Eréndira
AU - Cruz, Alejandro
AU - Contreras, Rosalinda
AU - Tlahuext, Hugo
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1996
Y1 - 1996
N2 - 1,3,2-Benzimidazaborole, 1,3,2-benzoxaborole, and 1,3,2-benzothiazaborole were synthesized from the corresponding 2-benzazole N-BH3 and 2-benzazole S-BH3 adducts through a reductive transposition from the isolobal fragment X-C(sp2) = N(sp2) - B(sp3) (X = N, O, S) to the fragment X-B(sp2) = N(sp2) - C(sp3). N-BH3 substitution shifts to lower frequencies 4-H, C-3a, and C-7a resonances. The X-ray diffraction analysis of 2-(o-methoxyphenyl)benzothiazole N-BH3 adduct is reported. Two new tetracyclic boron-bridged compounds were observed as by-products (6,9-(ethyl)-diaza-2-oxa-1-bora[3,4,7,8]-dibenzobycyclo[4.3.0]-nona-3,7-diene, 6d, and 8-aza-9-oxa-2-thia-1-bora-[3,4,7,8]dibenzobycyclo[3.4.0]nona-3,7-diene, 15d, when 2-(o-methoxyphenyl)-1-ethylbenzimidazole-BH3 6b and 2-(o-methoxyphenyl)-benzothiazole-BH3 15b adducts were heated.
AB - 1,3,2-Benzimidazaborole, 1,3,2-benzoxaborole, and 1,3,2-benzothiazaborole were synthesized from the corresponding 2-benzazole N-BH3 and 2-benzazole S-BH3 adducts through a reductive transposition from the isolobal fragment X-C(sp2) = N(sp2) - B(sp3) (X = N, O, S) to the fragment X-B(sp2) = N(sp2) - C(sp3). N-BH3 substitution shifts to lower frequencies 4-H, C-3a, and C-7a resonances. The X-ray diffraction analysis of 2-(o-methoxyphenyl)benzothiazole N-BH3 adduct is reported. Two new tetracyclic boron-bridged compounds were observed as by-products (6,9-(ethyl)-diaza-2-oxa-1-bora[3,4,7,8]-dibenzobycyclo[4.3.0]-nona-3,7-diene, 6d, and 8-aza-9-oxa-2-thia-1-bora-[3,4,7,8]dibenzobycyclo[3.4.0]nona-3,7-diene, 15d, when 2-(o-methoxyphenyl)-1-ethylbenzimidazole-BH3 6b and 2-(o-methoxyphenyl)-benzothiazole-BH3 15b adducts were heated.
UR - http://www.scopus.com/inward/record.url?scp=0001074311&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1098-1071(199610)7:5<323::AID-HC7>3.3.CO;2-P
DO - 10.1002/(SICI)1098-1071(199610)7:5<323::AID-HC7>3.3.CO;2-P
M3 - Artículo
AN - SCOPUS:0001074311
SN - 1042-7163
VL - 7
SP - 323
EP - 335
JO - Heteroatom Chemistry
JF - Heteroatom Chemistry
IS - 5
ER -