2039-93-2Relevant articles and documents
STRUCTURES OF ISOMERIC ANIONS IN THE GAS PHASE: ARYLLALLYL AND ARYLCYCLOPROPYL ANIONS.
Andrist,DePuy,Squires
, p. 845 - 850 (1984)
The isomeric 1-phenylcyclopropyl and 2-phenylallyl anions have been prepared in the gas phase by proton-abstraction reactions. They have been shown to be distinct, noninterconverting species by their differing reactions with D//2O, O//2, and N//2O. The 2-methyl-1-phenylcyclopropyl and 1-methyl-2-phenylallyl anions are also shown to react differently with these reagents. However, in the presence of H//2O the 1-methyl-2-phenylallyl anion is converted to the 1-methyl-1-phenylallyl anion by proton addition and reabstraction. The utility of these and other reagents for determining ion structure in the gas phase is discussed.
Cram,Sahyun
, p. 1257,1263 (1963)
1,3-Difunctionalization of β-alkyl nitroalkenes via combination of Lewis base catalysis and radical oxidation
Wang, Ye,Zheng, Lei,Shi, Xiaodong,Chen, Yunfeng
supporting information, p. 886 - 889 (2021/02/01)
Upon treatment with a Lewis base catalyst, β-alkyl-substituted nitroalkenes could be readily converted into allylic nitro compounds. Examples of either C-1 or C-3 functionalization methods have been reported through nitro-elimination, giving alkene products. In this work, successful 1,3-difunctionalization was achieved through a synergetic Lewis base catalysis and TBHP radical oxidation, giving vinylic alkoxyamines in good to excellent yields. This work further extended the general synthetic application of β-alkyl nitroalkenes.
Cobalt(II)-Catalyzed Stereoselective Olefin Isomerization: Facile Access to Acyclic Trisubstituted Alkenes
Zhang, Sheng,Bedi, Deepika,Cheng, Lu,Unruh, Daniel K.,Li, Guigen,Findlater, Michael
supporting information, p. 8910 - 8917 (2020/12/23)
Stereoselective synthesis of trisubstituted alkenes is a long-standing challenge in organic chemistry, due to the small energy differences between E and Z isomers of trisubstituted alkenes (compared with 1,2-disubstituted alkenes). Transition metal-catalyzed isomerization of 1,1-disubstituted alkenes can serve as an alternative approach to trisubstituted alkenes, but it remains underdeveloped owing to issues relating to reaction efficiency and stereoselectivity. Here we show that a novel cobalt catalyst can overcome these challenges to provide an efficient and stereoselective access to a broad range of trisubstituted alkenes. This protocol is compatible with both mono- and dienes and exhibits a good functional group tolerance and scalability. Moreover, it has proven to be a useful tool to construct organic luminophores and a deuterated trisubstituted alkene. A preliminary study of the mechanism suggests that a cobalt-hydride pathway is involved in the reaction. The high stereoselectivity of the reaction is attributed to both a π-πstacking effect and the steric hindrance between substrate and catalyst.