Applications of Baylis–Hillman adducts: a simple, convenient, and one-pot synthesis of 3-benzoylquinolines

A simple and convenient synthesis of 3-salicyloylquinoline-4-carboxylic esters from chromone and isatin

A simple and convenient synthesis of 3-salicyloylquinoline-4-carboxylic esters has been developed through an AlCl3-catalyzed reaction of easily available Baylis-Hillman adducts from chromones and isatin-derivatives. This reaction involves esterification, cyclization and ring opening in a one-step process, and provides an efficient approach for easy access to a series of valuable salicyloylquinoline derivatives with high yields. Moreover, this protocol offers several advantages, such as availability of starting materials, economic availability, operational simplicity and mild reaction conditions.

The Baylis–Hillman reaction: a new continent in organic chemistry – our philosophy, vision and over three decades of research

This mini review describes in brief the way in which our research has contributed towards the development of the Baylis–Hillman reaction as a powerful tool in synthetic chemistry, offering unending opportunities and intellectual challenges to understand and address the present day requirements in the area of organic chemistry.

Syntheses of 4-Indolylquinoline Derivatives via Reductive Cyclization of Indolylnitrochalcone Derivatives by Fe/HCl

An easy and efficient procedure for the synthesis of 4-indolylquinoline derivatives is described. This process involves two steps, the first of which is the Michael addition of indole to nitrochalcones promoted by sulfamic acid under solvent free conditions and the second step is a reductive cyclization of the indolylnitrochalcone intermediates to 4-indolylquinoline derivatives by Fe/HCl in ethanol. In both steps, the reactions are clean and the yields of products are high.

The reaction of porphyrins with α,β-acetylenic ketone/ester (Morita-Baylis-Hillman) promoted by MgI2 and subsequent Sonogashira coupling reactions

The stereoselective synthesis of (Z)-β-iodovinyl ketones/esters of Morita-Baylis-Hillman (MBH) porphyrin adducts has been achieved with a tandem formation of C - C and C - I bonds in a three-component reaction. The reaction is promoted by MgI 2 as a Lewis acid, as well as an iodine source for a Michael-type addition. The MBH adducts are efficiently oxidized to the corresponding ketones with Dess-Martin periodinane (DMP). These scaffolds are further used in a palladium-catalyzed Sonogashira carbon-carbon coupling reaction to obtain highly extended porphyrin systems.

An efficient ultrasound-promoted synthesis of the Baylis-Hillman adducts catalyzed by imidazole and L-proline

A convenient protocol was developed for the synthesis of the Baylis-Hillman adducts in the presence of weak Lewis base and l-proline at room temperature under ultrasound irradiation. This method provided the products in good to high yields (65-90%) and reasonable reaction times.

A highly alpha-regioselective AgOTf-catalyzed nucleophilic substitution of the Baylis-Hillman acetates with indoles

An efficient method for highly alpha-regioselective nucleophilic substitution of the Baylis-Hillman acetates with indoles catalyzed by AgOTf in high yields (72-99%) has been developed. Reductive cyclization of the substitution products furnished the azepinoindole derivatives in good yields (up to 93%).

The Baylis–Hillman approach to quinoline derivatives

Baylis-Hillman reactions of 2-nitrobenzaldehydes with various activated alkenes afford adducts that undergo reductive cyclisation to quinoline derivatives. The chemo- and regioselectivity of cyclisation appears to be influenced by the choice of both the substrate and the reagent system, and competing reactions have been observed.