Convenient synthesis of disubstituted tacrine derivatives via electrophilic and copper induced reactions was written by Ekiz, Makbule;Tutar, Ahmet;Okten, Salih. And the article was included in Tetrahedron in 2016.Application of 68385-95-5 This article mentions the following:
The bromination of 2-aminobenzonitrile with mol. bromine (2 equiv) furnished 2-amino-3,5-dibromobenzonitrile in 98% yield. One-pot syntheses are described for dibromotacrine derivatives, e.g., I (Y = CH2), utilizing Friedlander reactions. A convenient route is described for disubstituted derivatives of tacrines from dibromotacrine I (Y = CH2, CH2CH2) (II) by various substitution reactions. Several disubstituted tacrines were synthesized by treatment of II with n-BuLi followed by trapping with an electrophile [Si(Me)3Cl, S2(Me)2]. Both were converted to the corresponding cyano derivatives III (X = Br, Y = CH2; X = CN, Y = CH2; X = CN, CH2CH2) via copper-assisted nucleophilic substitution reactions in moderate yields (30%, 50%, and 60%, resp.). Copper-induced nucleophilic substitution of dibromide II (Y = CH2CH2) with NaOMe afforded mono-methoxide IV in 25% yield. In the experiment, the researchers used many compounds, for example, 2-Amino-3,5-dibromobenzonitrile (cas: 68385-95-5Application of 68385-95-5).
2-Amino-3,5-dibromobenzonitrile (cas: 68385-95-5) belongs to nitriles. The R-C-N bond angle in and nitrile is 180° which give a nitrile functional group a linear shape. Both the carbon and the nitrogen are sp hydridized which leaves them both with two p orbitals which overlap to form the two π bond in the triple bond. In conventional organic reductions, nitrile is reduced by treatment with lithium aluminium hydride to the amine. Reduction to the imine followed by hydrolysis to the aldehyde takes place in the Stephen aldehyde synthesis, which uses stannous chloride in acid.Application of 68385-95-5
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts