An efficient synthesis of 3-arylmethyl-7,8-dihydro-6H-chromene-2,5-diones from Baylis–Hillman adduct acetates under solvent-free conditions

Application of cyclohexane-1,3-diones for six-membered oxygen-containing heterocycles synthesis

Cyclohexan-1,3-dione derivatives are versatile scaffolds for the synthesis of a variety of value-added organic molecules including heterocycles and natural products. Six-membered oxygen heterocycles prepared from cyclohexan-1,3-diones are of much importance as they are intermediate for the synthesis of a number of natural products and several other valuable bioactive molecules which shows anti-viral, anti-bacterial, analgesic, antimalarial, anti-inflammatory, anti-allergic, anti-tumor and anti-cancer activities. These advantages have inspired us to write a detailed survey on the newly developed methods which are very essential in the construction of six-membered oxygen heterocycles. Further, the versatility in the chemistry of cyclohexan-1,3-dione and its derivatives is due to the presence of highly active methylene moiety and its active di-carbonyl groups. Recently, reactions of cyclohexane-1,3-dione and its derivatives with other substrates for instance aldehydes, malononitriles, NMSM, chalcones, isatin etc. have been established for the construction of a variety of six-membered oxygen heterocycles. The studies reported in this review article involved the synthesis of six-membered oxygen-containing heterocycles which includes 4H-chromen-5(6H)-one, 2H-xanthen-1(9H)-one, 2H-xanthen-1,8(5H,9H)-dione, 6H-chromen-2,5-dione derivatives and natural products having six-membered oxygen heterocycles from cyclohexane-1,3-dione and its derivatives as one of the substrate.

Fast, Microwave-Promoted One-Pot Synthesis of Bicyclic Pyrimidones from Baylis-Hillman Adducts

Two types of fused pyrimidones, 3-substituted-7-chloro-4H -pyrimido[1,2-b]pyridazin-4-ones and 6-substituted-5H-thiazolo-[3,2-a]pyrimidin-5-ones were easily prepared from Baylis-Hillman adduct acetates under microwave irritation in high yields.

One-Pot Synthesis of New Type Aza- Baylis–Hillman Adducts from Chlorovinyl Aldehydes under Solvent-Free Condition

A series of new type aza- Baylis–Hillman adducts were prepared in moderate yields by one-pot treatment of chlorovinyl aldehydes, benzenesulfonamides and activated olefins under solvent-free condition. The chlorovinyl aldehydes were obtained via chloroformylation of ketones using bis(trichloromethyl)carbonate(BTC)/DMF system.