82645-20-3Relevant articles and documents
Bromomethyl Silicate: A Robust Methylene Transfer Reagent for Radical-Polar Crossover Cyclopropanation of Alkenes
Luo, Wenping,Fang, Yewen,Zhang, Li,Xu, Tianhang,Liu, Yongjun,Li, Yan,Jin, Xiaoping,Bao, Jiakan,Wu, Xiaodong,Zhang, Zongyong
supporting information, p. 1778 - 1781 (2020/03/11)
A general protocol for visible-light-induced cyclopropanation of alkenes was developed with bromomethyl silicate as a methylene transfer reagent, offering a robust tool for accessing highly valuable cyclopropanes. In addition to α-aryl or methyl-substituted Michael acceptors and styrene derivatives, the unactivated 1,1-dialkyl ethylenes were also shown to be viable substrates. Apart from realizing the cyclopropanation of terminal alkenes, the methyl transfer reaction has been further demonstrated to be amenable to the internal olefins. The photocatalytic cyclopropanation of 1,3-bis(1-arylethenyl)benzenes was also achieved, giving polycyclopropane derivatives in excellent yields. With late-stage cyclopropanation as the key strategy, the synthetic utility of this transformation was also demonstrated by the total synthesis of LG100268.
A Novel Class of Tunable Zinc Reagents (RXZnCH2Y) for Efficient Cyclopropanation of Olefins
Lorenz, Jon C.,Long, Jiang,Yang, Zhiqiang,Xue, Song,Xie, Yinong,Shi, Yian
, p. 327 - 334 (2007/10/03)
A class of zinc reagents (RXZnCH2Y) generated with an appropriate organozinc is very effective for the cyclopropanation of olefins. The reactivity and selectivity of these reagents can be regulated by tuning the electronic and steric nature of the RX group on Zn. A reasonable level of enantioselectivity was obtained for the cyclopropanation of unfunctionalized olefins when a chiral (iodomethyl)zinc species was used, providing a valuable approach for the asymmetric cyclopropanation of unfunctionalized olefins.
Photochemistry of Phenyl-Substituted Benzobicyclohex-2-enes. A Reverse Di-?-methane Rearrangement
Lamberts, Joseph J. M.,Laarhoven, Wim H.
, p. 2202 - 2206 (2007/10/02)
The photochemical rearrangements of phenyl-substituted benzobicyclohex-2-enes can generally be explained by assuming that homolytic fission of that cyclopropane bond which leads to the most stable diradical is the primary step.The final products are formed by 1,2 hydrogen shifts in the intermediate.An exception to this general pattern was observed with 5-phenylbenzobicyclohex-2-ene (5).The photoproducts of 5 could only be explained by assuming reverse di-?-methane rearrangements followed by 1,3 hydrogen shifts.It is argued that this reaction path is followed because of the high rate to the back-reaction of the homolytic bond fission of 5.