109541-27-7Relevant academic research and scientific papers
Thermal rearrangements of 3,3-spiroalkylated pyrazoles: Ring expansion and novel cases of sequential 1,5-shifts
Yen, Yao-Pin,Chen, Shih-Feng,Heng, Zan-Cheng,Huang, Jen-Chieh,Kao, Li-Chun,Lai, Ching-Cheng,Liu
, p. 1859 - 1871 (2001)
A 3,3-spiro-(cyclopentyl)pyrazole containing electron withdrawing ester groups undergoes readily ring expansion in the form of the van Alphen-Huettel rearrangement. Subsequent post van Alphen-Huettel rearrangement involved a sequence of 1,5-shifts different from that suggested earlier. Reactive intermediates have been isolated and identified. The corresponding phenyl analog does not exhibit post van Alphen-Huettel rearrangement. A rationale for the different behavior is offered. X-Ray crystallography has been applied to differentiate between structurally similar product.
4,5-DIPHENYLIMIDAZOLES FROM THE CYCLIZATION OF BENZIL N-ALKYLMONOHYDRAZONES
Collibee, William L.,Anselme, Jean-Pierre
, p. 655 - 662 (2007/10/02)
The thermal cyclization of monodisubstituted hydrazones (1) affords the corresponding N-substituted-4,5-diphenylimidazoles in good to excellent yields; possible mechanisms for this unusual cyclization are presented.
