A series of functionalized 2,3-dihydro-1,4-benzoxazines were obtained in moderate to excellent yields via domino [5 + 1] annulations of 2-halo-1,3-dicarbonyl compounds 2 with imines 1 under mild conditions and the application of this method in the synthesis of bioactive analogues, such as functionalized tetracyclic-1,4-benzoxazines which contain two new heterocyclic rings and one quaternary car...

[reaction: see text]. Synthesis of novel dithiane-spiro-crown ethers starting from 5,5-di(hydroxymethyl)-1,3-dithiane is developed. These compounds can be used as building blocks to assemble photolabile bis-crown ethers via addition to dicarbonyl-containing tethers, e.g., isophthalic aldehyde. It is found that unlike their mono-crown precursors such bidentate bis-crowns are capable of efficient...

in this work, the efficiency, generality and applicability of new bronsted acidic ionic liquid (bail) 1-methyl-3-(2-(sulfooxy)ethyl)-1h-imidazol-3-ium chloride {[msei]cl} as heterogeneous and green catalyst for organic transformations are studied. herein, the following one-pot multi-component reactions in the presence of [msei]cl are investigated: (i) the synthesis of quinoxaline derivatives fr...

In order to facilitate oxidative addition chemistry of fac-coordinated rhodium(I) and iridium(I) compounds, carbene–bis(oxazolinyl)phenylborate proligands have been synthesized and reacted with organometallic precursors. Two proligands, PhB(OxMe2)2(ImtBuH) (H[1]; OxMe2 = 4,4-dimethyl-2-oxazoline; ImtBuH = 1-tert-butylimidazole) and PhB(OxMe2)2(ImMesH) (H[2]; ImMesH = 1-mesitylimidazole), are de...

Dicarbonyls are known to be important precursors of so-called atmospheric brown carbon, significantly affecting aerosol optical properties and radiative forcing. In this systematic study we report the formation of light-absorbing nitrogen containing compounds from simple 1,2-, 1,3-, 1,4-, and 1,5-dicarbonyl + amine reactions. A combination of spectrophotometric and mass spectrometric techniques...

A new disconnection toward tri- and tetrasubstituted furans has been conceptualized and demonstrated. A mild, base-mediated reaction of an allenoate pronucleophile with α-halo ketones/dicarbonyl compounds results in a Csp2-alkylation/enolization/O-vinylation sequence to ultimately afford substituted furan derivatives. The reaction offers a broad scope, provides a facile access to alkyl and aryl...

An unprecedented stereoselective organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence between β-dicarbonyl compounds, β-nitroalkenes and 4-nitro-5-styrylisoxazoles sequentially catalyzed by low loading of a squaramide catalyst and an achiral base has been developed. The protocol opens an efficient entry to isoxazole bearing cyclohexanes with six consecutive stereogenic centers including one ...

Background and Objective: A Simple, Green and efficient procedure for the synthesis of 4-aryl-3, 4-dihydropyrimidine-2(1H)-ones/thione (Biginelli reaction) from 1, 3-dicarbonyl compound, substituted aldehydes and urea/thiourea in the presence of Sodium Dodecyl Sulphate (SDS), a novel catalyst has been introduced in this study. Materials and Methods: The structures of these compounds have been c...