Tandem synthesis of quinazolinone scaffolds from 2-aminobenzonitriles using aliphatic alcohol–water system

Abstract

Functionalized bipyridine based Ru(II) complex catalyzed tandem synthesis of quinazolinones from 2-aminobenzonitriles is reported here utilizing aliphatic alcohol–water system.

Visible‐Light‐Induced Photocatalyst‐Free Oxidative Cyclization of Primary Alcohols by Selectfluor via HAT Process: Synthesis of Quinazolinones and Benzothiadiazines

“…These scaffolds have showed wide range of pharmacological properties such as anti‐bacterial, anti‐malarial, anti‐viral, anti‐cancer, anti‐hypertension, anti‐diabetes and anti‐inflammatory [2–5] . Owing to the immense significance of scaffolds, the various synthetic methodologies has been established, [6–9] Among them, the one‐pot direct oxidative condensation (e. g., dehydrogenative cyclization) of primary alcohols with o ‐aminobenzamides and o ‐aminobenzenesulfonamides have attracted more attention due to the elimination of hydrogen gas and H 2 O only generated as chemical waste [10–13] . Various homogeneous and heterogeneous catalysts have been employed for oxidation followed by condensation of primary alcohols [14] .…”

“…[2][3][4][5] Owing to the immense significance of scaffolds, the various synthetic methodologies has been established, [6][7][8][9] Among them, the one-pot direct oxidative condensation (e. g., dehydrogenative cyclization) of primary alcohols with o-aminobenzamides and o-aminobenzenesulfonamides have attracted more attention due to the elimination of hydrogen gas and H 2 O only generated as chemical waste. [10][11][12][13] Various homogeneous and heterogeneous catalysts have been employed for oxidation followed by condensation of primary alcohols. [14] Although, the activation of α C(sp 3 )À H of alcohols via hydrogen atom transfer for oxidative condensation under ambient conditions is still challenging.…”

“…There is no obvious effect on the yield of 3 a in different amount of selectfluor (Table 1, entries 9 and 10). Control experiments reveals that selectfluor, TFA, light and nitrogen are need to furnish the oxidative cyclization reaction (Table 1, entries [11][12][13][14].…”

Alkyl Phosphine Free, Metal‐Ligand Cooperative Complex Catalyzed Alcohol Dehydrogenative Coupling Reactions

“…Recently, Kundu group demonstrated an efficient protocol for the synthesis of quinazolinone using aliphatic alcohol [40] . Initially, a wide variety of quinazolinones was synthesized by the dehydrogenative coupling of 2‐aminobenzamides and alcohols, using complex 11 a (Scheme 20).…”

“…Recently, Kundu group demonstrated an efficient protocol for the synthesis of quinazolinone using aliphatic alcohol. [40] Initially, a wide variety of quinazolinones was synthesized by the dehydrogenative coupling of 2-aminobenzamides and alcohols, using complex 11 a (Scheme 20). Next, a tandem protocol was developed to prepare quinazolinone directly from 2-aminobenzonitrile using aliphatic alcohol-water system.…”