137869-22-8Relevant articles and documents
Regio- and Chemoselective Kumada-Tamao-Corriu Reaction of Aryl Alkyl Ethers Catalyzed by Chromium under Mild Conditions
Cong, Xuefeng,Tang, Huarong,Zeng, Xiaoming
supporting information, p. 14367 - 14372 (2015/12/01)
Acting as an environmentally benign synthetic tool, the cross-coupling reactions with aryl ethers via C-O bond activation have attracted broad interest. However, the functionalizations of C-O bonds are mainly limited to nickel catalysis, and selectivity has long been a prominent challenge when several C-O bonds are present in the one molecule. We report here the first chromium-catalyzed selective cross-coupling reactions of aryl ethers with Grignard reagents by the cleavage of C-O(alkyl) bonds. Diverse transformations were achieved using simple, inexpensive chromium(II) precatalyst combining imino auxiliary at room temperature. It offers a new avenue for buildup functionalized aromatic aldehydes with high efficiency and selectivity.
Regiospecific synthesis of polysubstituted naphthalenes via oxazoline-mediated nucleophilic aromatic substitutions and additions
Gant, Thomas G.,Meyers
, p. 1010 - 1015 (2007/10/02)
An efficient procedure for the selective functionalization of several positions of 2-methoxynaphthalene is described. Nucleophilic aromatic substitutions were carried out by displacing both a methoxy group and a neutral amine ortho to an oxazoline 6. 4-Substituted naphthalenes 8 were obtained from nucleophilic aromatic addition of an allyllithium species to a position para to the oxazoline 6. The resultant dihydronaphthalenes were converted to the fully aromatic systems 9 or alternatively substituted in the 2-position to form 10. Reductive cleavage of the oxazoline moities in 7 and 9 proceeded smoothly, producing the substituted naphthaldehydes 11.
