The NHC-catalyzed reactions of ortho electron-deficient vinyl substituted arylaldehydes with nitrosoarenes were studied. The reactions produced multifunctional 2,3-benzoxazin-4-ones in good to excellent yields via a cascade aza-benzoin reaction between aldehyde and nitroso groups followed by an intramolecular oxo-Michael addition. The resulting 1-acetate substituted 2,3-benzoxazinones were tran...

In this work several molecular properties of symmetrically disubstituted formaldehyde and thioformaldehyde have been studied using a quantum chemistry approach based on density functional theory. Five-membered heteroaromatic rings containing a single group 16 heteroatom were taken into account as the substituents (i.e., furan-2-yl, thiophen-2-yl, selenophen-2-yl, tellurophen-2-yl, and the exper...

Copper-catalyzed aerobic oxidative coupling of arylboronic acid derivatives and heteroatom nucleophiles is a highly useful method for the formation of aryl-heteroatom bonds. Mechanistic studies reveal that this reaction proceeds via an "oxidase"-style mechanism. Kinetic and spectroscopic studies establish that transmetalation of the aryl group from boron to Cu(II) is the turnover-limiting step ...

Based on our contemporary studies on the structures of biologically active molecules, we focus our attention on the aliphatic chain and its conformation. That flexible spacer definitely influenced the balanced position of all pharmacophoric points in molecules of biological ligands. The one atomic linker and two or three atomic spacers with one heteroatom X = O, S, CH2, NH have been taken into ...

Ruthenium-catalyzed cyclization of 1,6-allenynes occurs via the addition of heteroatom nucleophiles to ruthenacyclopentenes, providing functionalized 1,2-bisalkylidenecyclopentanes in a highly regio- and stereoselective manner.

Equatorial/axial conversion in piperidine and phosphorinane with different substituents wereinvestigated with great details. Three possible routes, i.e. heteroatom inversion and two ring inversiontype were considered. Ring conversion can occur via two pathways one starts with ring flatteningfrom the heteroatom site (nitrogen in piperidine and phosphorous in phosphorinane) and the otherinitiates...

equatorial/axial conversion in piperidine and phosphorinane with different substituents wereinvestigated with great details. three possible routes, i.e. heteroatom inversion and two ring inversiontype were considered. ring conversion can occur via two pathways one starts with ring flatteningfrom the heteroatom site (nitrogen in piperidine and phosphorous in phosphorinane) and the otherinitiates...

The search for and exploitation of efficient catalytic systems for selective conversion of furfural into various high value-added chemicals remains a huge challenge for green synthesis in the chemical industry. Here, novel Pt nanoparticles supported on bamboo shoot-derived porous heteroatom doped carbon materials were designed as highly active catalysts for controlled hydrogenation of furfural ...

Several new 4,5-dihydroimidazoles (and the corresponding imidazolium salts) carrying heteroatom substituents at C-2 have been prepared from the corresponding tetrahydroimidazol-2ones and/or -thiones.

N atom, thus providing carbenes derived from pyrazolium, isothiazolium, and even quinolinium salts that contain a stabilizing heteroatom in a remote position (G-J in Figure 1). Recently, carbenes such as K, which are comprised of only one heteroatom and lack delocalization through the heterocycle, have been discovered as versatile ligands, thus constituting another important class of carbenes w...