Sequential one-pot and three-component reactions of an N-heterocyclic carbene to form 4-(1,2,4-triazol-5-ylidene)pyrrolidine-2,5-diones: a tandem umpolung/annulation sequence via deoxy-Breslow intermediates

• Published in: Tetrahedron Vol. 68; no. 47; pp. 9836 - 9841
• Main Authors: Matsuoka, Shin-ichi, Tochigi, Yusuke, Takagi, Koji, Suzuki, Masato
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 25.11.2012; Elsevier
• Subjects: Carbenes; Chemical reactions; Chemistry; Chemistry, Organic; Deoxy-Breslow intermediate; Dimethyl; Esters; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with only one n hetero atom and condensed derivatives; Heterocyclic compounds with several n hetero atoms in the same ring, in separated rings or in fused rings; Isocyanates; N-Heterocyclic carbene; Organic chemistry; Phenyls; Physical Sciences; Polymethyl methacrylates; Preparations and properties; Science & Technology; Sequential one-pot reaction; Three-component reaction; Umpolung; Umpolung; Three-component reaction; N-Heterocyclic carbene; ZMGMXNXGDAQUCZ-YCNYHXFESA-N; Deoxy-Breslow intermediate; JVPVFNSDGAZPHU-NWBJSICCSA-N; IUZCHQJQGOUKOY-RFBIWTDZSA-N; Sequential one-pot reaction; IIPWWZXQCSSXRB-OHYPFYFLSA-N; DONFLGNUBQSSBN-UHFFFAOYSA-M; XTSHYDOQMMUMTO-OHYPFYFLSA-N; WJOBHFMULCGIRA-LCUIJRPUSA-N; HHYHLODEYCFQFY-HYOGKJQXSA-N; MKKVJAKRYYVGQN-UHFFFAOYSA-M; DIJKSGBJUVAXLF-OHYPFYFLSA-N; STABLE CARBENE; PYRIMIDINE-DERIVATIVES; TO-TAIL DIMERIZATION; CONJUGATE-ADDITION; 1,3,4-TRIPHENYL-4,5-DIHYDRO-1H-1,2,4-TRIAZOL-5-YLIDENE; ALDEHYDES; HIGHLY EFFICIENT; THIAZOLIUM SALTS; MULTICOMPONENT REACTIONS; FACILE SYNTHESIS; One pot reaction; N-heterocyclic carbene; Organic isocyanate; Stoichiometry; Crotonic acid; Multicomponent reaction; Nitrogen heterocycle; Selectivity; 1,2,4-Triazole derivative; Tandem reaction; Pyrrolidine derivatives; Unsaturated compound; Annelation; Ester; Imide; Isolation; Polarity inversion; Methyl methacrylate
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2012.08.076

The tandem sequence of the umpolung of α,β-unsaturated esters by an N-heterocyclic carbene (NHC) followed by annulation is demonstrated. The deoxy-Breslow intermediates are selectively generated from the reaction of NHC with methyl methacrylate, dimethyl itaconate, or methyl crotonate. Subsequently, they undergo annulation with isocyanates to give 4-(1,2,4-triazol-5-ylidene)pyrrolidine-2,5-diones in good isolated yields. In addition, the stoichiometric three-component reaction of NHC, methyl methacrylate, and phenyl isocyanate proceeded, accompanied by the formation of the 1:2 adduct of NHC with phenyl isocyanate. [Display omitted]