6990-68-7Relevant articles and documents
Chromium-Catalyzed Linear-Selective Alkylation of Aldehydes with Alkenes
Hirao, Yuki,Kanai, Motomu,Katayama, Yuri,Mitsunuma, Harunobu
supporting information, (2020/11/18)
We developed a chromium-catalyzed, photochemical, and linear-selective alkylation of aldehydes with alkylzirconium species generated in situ from a wide range of alkenes and Schwartz's reagent. Photochemical homolysis of the C-Zr bond afforded alkyl radicals, which were then trapped by a chromium complex catalyst to generate the alkylchromium(III) species for polar addition to aldehydes. The reaction proceeded with high functional group tolerance at ambient temperature under visible-light irradiation.
Olefin-assisted iron-catalyzed alkylation of aryl chlorides
Guelak, Samet,Gieshoff, Tim N.,Von Wangelin, Axel Jacobi
, p. 2197 - 2202 (2013/10/01)
A selective and operationally simple ironcatalyzed cross-coupling of aryl chlorides with alkylmagnesium halides has been developed. The reaction tolerates various functional groups and exhibits high chemoselectivity even in the presence of aryl bromides. Mechanistic studies indicate the essential role of the olefin substituent for substrate activation. Competing polymerization and reduction are effectively suppressed.
Chromium(ii)-mediated reactions of iodonium tetrafluoroborates with aldehydes: Umpolung of reactivity of diaryl-, alkenyl(aryl)-, and alkynyl(aryl)iodonium tetrafluoroborates
Chen, Da-Wei,Ochiai, Masahito
, p. 6804 - 6814 (2007/10/03)
The method described herein allows us, for the first time, to perform umpolung of reactivity of diaryl-, alkenyl(aryl)-, and alkynyl(aryl)iodonium tetrafluoroborates. The method involves generation of organochromium(III) species via reaction of iodonium salts with anhydrous chromium dichloride, followed by their nucleophilic addition to aldehydes to yield alcohols. In contrast to the reaction of aryl and alkenyl halides with chromium dichloride, these iodonium salts are so active that organochromium(III) could be generated without using a nickel catalyst. Substituent effects of unsymmetrically substituted diaryliodonium salts on the product profiles are in good agreement with the reported mode of decomposition of the intermediate unsymmetrical diaryliodanyl radicals. Alkenyl(mesityl)iodonium tetrafluoroborates undergo exclusive alkenylation of aldehydes with no signs of the formation of an arylation product.
