54696-03-6Relevant academic research and scientific papers
Facile synthesis of 2-benzoxazoles via CuI/2,2'-bipyridine catalyzed intramolecular C–O coupling of 2-haloanilides
Venu Saranya, Thachora,Rajan Sruthi, Pambingal,Anas, Saithalavi
, p. 297 - 307 (2019/01/18)
Development of newer methods for the synthesis of Benzoxazoles has of greater interest due to their wide range of biological activities and pharmaceutical importance. We herein report a facile and general method for the synthesis of 2-substituted Benzoxazoles via copper catalyzed intramolecular C–O cross-coupling of 2-haloanilides. A combination of CuI (5 mol%), 2,2'-bipyridine (10 mol%), Cs2CO3 (2 equiv.) in DMF solvent with 4 ? molecular sieves at 140 °C, illustrated the scope for tuning the reactivity of 2-haloanilides toward the selective formation of a series of 2-alkyl benzoxazole derivatives in moderate to good yields. This is the first systematic study using CuI/2,2'-Bipyridine as the catalytic system for the synthesis of 2-substituted Benzoxazoles. The outcome of the reaction was found to be significantly influenced by the aromatic and amide substituents of 2-haloanilides.
Multicomponent reactions of convertible isonitriles
Pirrung, Michael C.,Ghorai, Subir,Ibarra-Rivera, Tannya R.
experimental part, p. 4110 - 4117 (2009/09/25)
(Chemical Equation Presented) A new family of unsaturated isonitriles has been prepared by the base-promoted ring-opening of oxazoles, offering an alternative to the conventional formamide dehydration route. These compounds undergo the full complement of multicomponent reactions for which isonitriles are known and offer the desirable trait of giving amide products that readily participate in acyl substitution reactions (hence, they are convertible). Moreover, they do not have the objectionable odors for which isonitriles are typically known, making them more accessible as reagents for organic synthesis. One focus of the work is isonitriles bearing perfluorinated alkyl groups that enable the ready separation of such reagents from nonfluorinated reaction products using the "light" fluorous method of fluorous solid-phase extraction.
Carbon-carbon bond cleavage of diynes through the hydroamination with transition metal catalysts
Shimada, Tomohiro,Yamamoto, Yoshinori
, p. 6646 - 6647 (2007/10/03)
The C-C bond cleavage of terminal and internal diynes takes place readily in the presence of catalytic amounts of Ru3(CO)12 or Pd(NO3)2 and of 2-aminophenol, giving the corresponding benzoxazoles and ketones in good to high yields. There are two different modes of the bond cleavage: (a) an alkyne C-C triple bond is cleaved, and (b) the C-C single bond between the two alkyne groups is cleaved. Copyright
Photochemical and Thermal Reactions of Aromatic Schiff Bases
Tauer, Erich,Grellmann, Karl H.
, p. 4252 - 4258 (2007/10/02)
The photochemical and thermal reactions of aromatic Schiff bases (SB) prepared from o-aminophenol and aldehydes and from o-aminophenol and ketones are compared.All SB's are converted by light into the corresponding benzoxazolines.For the SB's derived from aldehydes, benzoxazoline formation is a prerequisite to convert them by a second photon into benzoxazoles.In some cases oxygen is not required for this second reaction step.SB's derived from ketones are converted into benzoxazoles by the absorption of just one photon, but only in the presence of oxygen and only if the aliphatic residue R1 of the N=C(R1R2) bridge contains at least two carbon atoms.A radical mechanism is proposed for this reaction.Benzoxazine formation is observed in some cases as a thermal side reaction.The photochemical reactions of the latter were also investigated.
