5099-95-6Relevant articles and documents
-
Sheehan,Izzo
, (1949)
-
Synthesis of new tricyclic 5,6-dihydro-4H-benzo[b][1,2,4]tri-azolo[1,5-d][1,4]diazepine derivatives by [3+ + 2]-cyclo-addition/rearrangement reactions
Luan, Lin-bo,Song, Zi-jie,Li, Zhi-ming,Wang, Quan-rui
supporting information, p. 1826 - 1833 (2018/08/21)
Two new series of tricyclic heterocycles, namely 5,6-dihydro-4H-benzo[b][1,2,4]triazolo[1,5-d][1,4]diazepinium salts 10 and the related neutral, free bases 13 were synthesized from 4-acetoxy-1-acetyl-4-phenylazo-1,2,3,4-tetrahydroquinolines 8 and nitriles 9 in the presence of aluminium chloride by the [3+ + 2]-cycloaddition reaction of the in situ generated azocarbenium intermediates 14 followed by a ring-expansion rearrangement. In the rearrangement reaction, the phenyl substituent in the initially formed spiro-triazolium adducts 16 underwent a [1,2]-migration from C(3) to the electron-deficient N(2). This led to the ring expansion from 6-membered piperidine to 7-membered diazepine furnishing the tricyclic 1,2,4-triazole-fused 1,4-benzodiazepines.
Ruthenium-Pincer-Catalyzed Hydrogenation of Lactams to Amino Alcohols
Chen, Jiangbo,Wang, Jiaquan,Tu, Tao
, p. 2559 - 2565 (2018/07/30)
By using the commercially available ruthenium pincer complex (Ru-MACHO-BH) as a catalyst, the challenging direct hydrogenation of lactams and analogues has been successfully accomplished to deliver corresponding value-added amino alcohols in good-to-excellent yields under mild reaction conditions. Remarkably, in addition to N-protected lactams, unprotected ones could also be readily reduced in the presence of a catalytic amount of weak base or even under neutral reaction conditions, which further highlights the broad substrate scope and the protocol efficiency.
