Synthesis of various substituted dibenzo[b,d]pyranones including amino acid derivatives by SRN1 methodology

Beugelmans, ReneBois-Choussy, MicheleChastanet, JacquelineLe Gleuher, MartineZhu, Jieping2010-11-252010-11-252010-11-25199310.3987/COM-93-6494https://infoscience.epfl.ch/handle/20.500.14299/58576An easy prepn. of the title compds. involving a SRN1 o-arylation of phenolates by o-bromobenzonitrile followed by SiO2-catalyzed lactonization is described. Activated or not activated phenols are efficient. Access to benzonaphthopyranones is exemplified by the reactions with 2-naphtholate. Reactions with chiral p-hydroxyphenylamino acid derivs. are also reported. Thus, irradn. of Ac-L-Tyr(Ac)-OMe and 2-bromo-4,5-dimethoxybenzonitrile in liq. NH3, followed by treatment with silica in CH2Cl2, gave 52% dibenzopyranyl amino ester I. [on SciFinder (R)]Amino acids Role: SPN (Synthetic preparation)PREP (Preparation) (dibenzopyranylprepn. via nucleophilic radical arom substitution reactions of phenol derivs. with bromobenzonitriles and silica-catalyzed cyclization); Cyclocondensation reaction (nucleophilic radical arom substitution reactions andof bromobenzonitriles with phenols and naphthols to dibenzopyranones); Phenols Role: RCT (Reactant)RACT (Reactant or reagent) (nucleophilic radical arom substitution reactions with bromobenzonitriles and silica-catalyzed cyclization to dibenzopyranones); Substitution reaction (homolyticof bromobenzonitriles with phenols and naphtholsand silica-catalyzed cyclization to dibenzopyranones)nucleophilic radical arom substitution phenolate; lactonization cyanophenylphenol; phenol cyanophenyl lactonization; dibenzopyranone; amino acid dibenzopyranylmethylSynthesis of various substituted dibenzo[b,d]pyranones including amino acid derivatives by SRN1 methodologytext::journal::journal article::research article