34815-66-2Relevant academic research and scientific papers
Iron Catalyzed Isomerization of α-Alkyl Styrenes to Access Trisubstituted Alkenes
Xu, Songgen,Liu, Guixia,Huang, Zheng
, p. 585 - 589 (2021/02/01)
Stereoselective isomerization of α-alkyl styrenes is accomplished using a new iron catalyst supported by phosphine-pyridine-oxazoline (PPO) ligand. The protocol provides an atom-efficient and operationally simple approach to trisubstituted alkenes in high
Highly Stereoselective Positional Isomerization of Styrenes via Acid-Catalyzed Carbocation Mechanism
Hu, Xiao-Si,He, Jun-Xiong,Zhang, Ying,Zhou, Jian,Yu, Jin-Sheng
supporting information, p. 2227 - 2233 (2021/06/28)
The first transition metal-free highly stereoselective positional isomerization of various α-alkyl styrenes through a carbocation mechanism triggered strategy is developed by using Al(OTf)3 as a hidden Br?nsted acid catalyst, which provides facile access to value-added acyclic tri- and tetra-substituted alkenes in good yields with high stereoselectivity under mild conditions. The practicality of this protocol is further highlighted by the gram-scale synthesis, high stereoselectivity, good functional group tolerance, and simple operation. Mechanistic studies support that Al(OTf)3 acts as a hidden Br?nsted acid catalyst and a carbocation intermediate is formed.
Cobalt-Catalyzed Migrational Isomerization of Styrenes
Zhao, Jiajin,Cheng, Biao,Chen, Chenhui,Lu, Zhan
supporting information, p. 837 - 841 (2020/01/31)
An efficient cobalt-catalyzed migrational isomerization of styrenes was developed using the thiazoline iminopyridine (TIP) ligand. This reaction is operationally simple and atom-economical using readily available starting materials to access trisubstituted alkenes. Even when using a 0.1 mol % catalyst loading, the reaction could be conducted in neat and completed in 1 h with excellent conversion and high E stereoselectivity.
Photochemistry of (o-Methylphenyl)alkenes and the Stereospecific Trapping of the Resulting o-Xylylenes
Hornback, Joseph M.,Barrows, Russel D.
, p. 4285 - 4291 (2007/10/02)
The photochemical behavior of a series of o-methylstyrenes with simple alkyl groups in the α or β positions was investigated in order to determine the synthetic potential of the resulting o-xylylenes.The major photochemical product of all the styrenes employed (1,9,10, and 11) was the corresponding o-xylylene.The o-xylylenes were trapped in acceptable yields by maleic anhydride to give the Diels-Alder adducts.In the case of 9 or 10 and 11 the o-xylylynes were produced stereoselectively and trapped stereospecifically to give 15 or 16 respectively.In the absence ofa dienophile or in the presence of a weak dienophile, such as cyclohexene, a slower isomerization of the o-methylstyrenes to the meta isomers was observed, presumably via a benzvalene intermediate.In addition, the o-xylylene produced from 9 or 10 and 11 underwent geometrical isomerization in the absence of maleic anhydride, resulting in the formation of 10 and 11 upon irradiation of 9 and vice versa.
