The first example of the palladium-catalyzed, three-component tandem reaction of 2-aminobenzonitriles, aldehydes, and arylboronic acids has been developed, providing a new approach for one-pot assembly of diverse quinazolines in moderate to good yields. A noteworthy feature of this method is the tolerance of bromo and iodo groups, which affords versatility for further synthetic manipulations. Preliminary
Preparation of Quinazolines via a 2+2+2 Annulation from Aryldiazonium Salts and Nitriles
作者:Mani Ramanathan、Shiuh-Tzung Liu
DOI:10.1021/acs.joc.7b01325
日期:2017.8.4
A (2+2+2) modular synthesis of multisubstituted quinazolines has been realized by the direct reaction of aryldiazonium salts with two equivalent of nitriles. Reaction of aryldiazonium salt with a nitrile provides the initial formation of a reactive nitrilium ion, which is attacked by another molecule of nitrile followed by electrophilic cyclization to deliver the desired product. Notable flexibility
Ru(II)-Catalyzed C–H Activation and Annulation Reaction via Carbon–Carbon Triple Bond Cleavage
作者:Rashmi Prakash、Bidisha R. Bora、Romesh C. Boruah、Sanjib Gogoi
DOI:10.1021/acs.orglett.8b00643
日期:2018.4.20
An unprecedented Ru(II)-catalyzed C–H activation and annulation reaction, which proceeds via C–C triple bond cleavage, is reported. This reaction of 2-phenyldihydrophthalazinediones with alkynes, which works most efficiently in the presence of bidented ligand 1,3-bis(diphenylphosphino)propane, affords good yields of substituted quinazolines.
The synthesis of 2,4-disubstituted quinazolines by a palladium-catalyzed reaction of arylboronic acids with N-(2-cyanoaryl)benzamides has been developed with moderate to excellent yields. The method shows good functional group tolerance. In particular, halogen and hydroxyl substituents, which are amenable for further synthetic elaborations, are well tolerated. Moreover, the present synthetic route