Upon combining phenylacetylene A3 with benzoyl chloride B1 in the presence of 2 mol % Cu(dmp)(BINAP)BF4 under blue light irradiation, the βchlorovinyl ketone 86 was obtained as a single regioisomer in 65% yield with excellent E-distereoselectivity (E:Z = 95:5; see SI for detailed optimization). Gratifyingly, para-and meta-alkyl substituted phenylacetylenes were suitable substrates and the ATRA products 87-90 were isolated in good yields and diastereoselectivity (Fig. ). The reaction yield was hampered by ortho substitution on the aryl motif (91) with increased steric hindrance, however, it did not affect the diastereoselectivity. Some valuable functional groups, such as halides (92 and 93), trifluoromethyl (94), ester (95), and aldehyde (96) were tolerated well both in terms of yield and E-selectivity. In the case of electron-rich arene alkynes, β-chlorovinyl ketones 97 and 98 were obtained in good yields but with notably decreased E-selectivity. Of note, 3thiophenylacetylene afforded the corresponding β-chlorovinyl ketone 98 with excellent E-selectivity. To further highlight the applicability of the methodology, phenylacetylenes derived from (±)-isoborneol and diacetone d-glucose furnished the desired β-chlorovinyl ketones 100 and 101, again with almost perfect E-selectivity (Fig. ). However, disubstituted alkynes such as 1-phenyl-1-propyne and unactivated alkynes such as 1-hexyne were found to be inactive towards this reaction.