129196-82-3Relevant articles and documents
Diastereoselective Diels-Alder Reaction of 2-Thienyl and 2-Furyl Substituted 3-Propenethioamides with Electron Deficient Dienophiles
Bogdanowicz-Szwed, Krystyna,Budzowski, Artur
, p. 97 - 108 (2004)
The hetero-Diels-Alder reaction of N-aryl-3-(2-thienyl)-2- propenethioamides with N-phenylmaleimide and maleimide yielded a mixture of endo- and exo-2-arylimino-4-(2-thienyl)tetrahydrothiopyran[2,3-c]pyrroles. Cycloaddition to diethyl fumarate required acylation and furnished a mixture of diastereoisomeric 5-(N-acetylphenylamino)-2,3-bis-(ethoxycarbonyl)-4-(2-thienyl) -3,4-dihydro-2H-thiopyrans. Reactions of 3-(2-furyl)-2-propenethioamides with N-arylmaleimides furnished the correspondent 2-arylimino-4-(2-furyl) tetrahydrothiopyran[2,3-c]pyrroles. In the cycloadditions of the heterodienes with N-arylmaleimides the endo-cycloadducts were formed as the major products.
Nickel(0) induzierte und katalysierte CC-Verknuepfungen zwischen Phenylisocyanat und vinylsubstituierten Heteroaromaten
Hoberg, Heinz,Guhl, Dieter,Betz, Peter
, p. 233 - 246 (2007/10/02)
Vinyl substituted heterocycles such as 2-vinylfuran (Ia) and 2-vinylpyridine (Ib) react with phenylisocyanate (II) in presence of (Lig)Ni0 (Lig = TCP) to form the tricyclohexylphosphane-5-azanickelacyclopentan-4-one derivatives (V).The structures and properties of these metallacycles are described.A catalytic 1/1 CC bond formation to give the α,β-unsaturated carboxylic acid amide X proceeds only with Ia (Lig = P(OiP)3) and not with Ib (Lig = PEt3, PPh3, P(OiP)3).Presumably, the different reactivities are not caused by electronic and/or steric factors of the 2-furyl- or 2-pyridyl-substituents, but by the donor properties of the N-atom in Ib.The N Ni interactions in the complex bis2-2-vinyl-μ-pyridine-nickel> (XIIb) can be detected by spectroscopic and crystal structure studies.