The author of 《Photocatalytic carbanion generation from C-H bonds – reductant free Barbier/Grignard-type reactions》 were Berger, Anna Lucia; Donabauer, Karsten; Koenig, Burkhard. And the article was published in Chemical Science in 2019. Electric Literature of C43H30F2N4 The author mentioned the following in the article:
A redox-neutral method for the generation of carbanions from benzylic C-H bonds in a photocatalytic Grignard-type reaction was reported. The combination of photo- and hydrogen atom transfer (HAT) catalysis enabled the abstraction of a benzylic hydrogen atom, generating a radical intermediate. This radical was reduced in situ by the organic photocatalyst to a carbanion, which was able to react with electrophiles such as aldehydes or ketones, yielding homobenzylic secondary and tertiary alcs. ArCR1R2C(OH)R3R4 [R1 = R2 = H, Me, R1 = H, R2 = Me; R3 = R4 = Me, Et, n-Bu, R3 = H, Me, R4 = Me, Et, i-Pr, etc; Ar = 2-thienyl, Ph, 4-MeOC6H4, etc.]. In the experiment, the researchers used many compounds, for example, 2,4,6-Tris(diphenylamino)-3,5-difluorobenzonitrile(cas: 1403850-00-9Electric Literature of C43H30F2N4)
2,4,6-Tris(diphenylamino)-3,5-difluorobenzonitrile(cas: 1403850-00-9) is cyanoarene-based donor-acceptor photocatalyst developed by the Zeitler group. While this catalyst has a balanced redox profile, allowing for its use in a variety of transformations, it stands out as the most reducing catalyst of the family.Electric Literature of C43H30F2N4
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts