On irradiation in methanol, aryloxyacetones gave 2-methylbenzofurans and the phenol formed by fission of the ArO–CH2 bond. meta-Substituted aryloxyacetones also formed dimethyl acetals by a photoreaction. Chloro-,bromo-, and nitro-substituents retarded or prevented the photoreaction. When p-methoxyphenoxyacetone was irradiated, the intermediate leading to a benzofuran was isolated and shown to be the product of ortho-rearrangement.
Palladium-Catalyzed C(sp<sup>3</sup>
)−H Arylation of Primary Amines Using a Catalytic Alkyl Acetal to Form a Transient Directing Group
作者:Sahra St John-Campbell、Alex K. Ou、James A. Bull
DOI:10.1002/chem.201804515
日期:2018.12.3
requires derivatization at nitrogen with a directinggroup. Transientdirectinggroups (TDGs) permit C−H functionalization in a single operation, without needing these additional steps for directinggroup installation and removal. Here we report a palladium catalyzed γ‐C−H arylation of amines using catalytic amounts of alkyl acetals as transientactivators (e.g. commercially available (2,2‐dimethoxyethoxy)benzene)