Nickel-Catalyzed Decarboxylative Acylation of Heteroarenes by sp<sup>2</sup>CH Functionalization
作者:Ke Yang、Cheng Zhang、Peng Wang、Yan Zhang、Haibo Ge
DOI:10.1002/chem.201402516
日期:2014.6.10
azole derivatives with α‐oxoglyoxylic acids has been developed. This work represents the first example of decarboxylative cross‐coupling reactions, in a CH bond functionalization manner, through nickel catalysis, and tolerates various functional groups. Additionally, this approach provides an efficient access to azole ketones, an important structural motif in many medicinal compounds with a broad
Abstract A new strategy has been developed for the construction of oxazoles from methyl ketones and TosMIC via self-sorting oxidative domino reaction strategy. In contrast to its usual reactivity as C–N≡C synthon in the synthesis of oxazoles, TosMIC was utilized as ammonium surrogate in the present method. The protocol is attractive in terms of readily available starting materials, metal and base free
Metal-Free sp3 C–H Functionalization: PABS/I2-Promoted Synthesis of Polysubstituted Oxazole Derivatives from Arylethanones and 2-Amino-2-alkyl/arylacetic Acid
nonmetal-catalyzed process for the synthesis of polysubstituted oxazoles from inexpensive and readily available α-amino acids and methyl ketones is established. This reaction is proposed to achieve oxidative cleavage of C(sp3 )–Hbonds, followed by decarboxylation and annulation. The mild reaction conditions employed in both cases enable the tolerance of a wide range of functional groups as well as high reaction
Direct Synthesis of 2,5-Disubstituted Oxazoles through an Iodine-Catalyzed Decarboxylative Domino Reaction
作者:Wei Xu、Ulrich Kloeckner、Boris J. Nachtsheim
DOI:10.1021/jo400753n
日期:2013.6.21
An efficient iodine-catalyzed synthesis of highly substituted oxazoles is presented. Starting from readily available aryl methylketones, β-keto esters, or styrenes, in combination with α-amino acids as amine-containing coupling partners, the corresponding 2-alkyl-5-aryl- substituted oxazoles were obtained in up to 80% yield via a decarboxylative domino reaction.
An efficient synthesis of a variety of 2,5-diaryloxazole derivatives via a rhodium-catalyzed annulation of triazoles and aldehydes is achieved. Various oxazole derivatives could be obtained in good to excellent yields. A concise synthesis of antimycobaterial natural products balsoxin and texamine has been achieved using this method.