A new base-promoted cyclization for the synthesis of substituted benzo[b]furans is described. This method is simple and inexpensive and gives good yields.
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http://dx.doi.org/10.1039/C2RA21302H | DOI Listing |
Chem Commun (Camb)
December 2024
Advanced Catalysis and Green Manufacturing Collaborative Innovation Center, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
A base-promoted cascade 5- cyclization/carboxylation of -alkynylsulfamides with CO has been accomplished, furnishing a variety of benzosultam-containing acrylates in good yields by using CO as the carboxylic source. Notably, in the case of substrates bearing a TMS-alkyne motif, the -dicarboxylation products were generated unprecedentedly.
View Article and Find Full Text PDFJ Org Chem
November 2024
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China.
The synthesis of multifunctionalized dihydropyridinones from aldehydes and ketones involves at least a three-step process, making route shortening a challenging task, especially in achieving a one-pot four-component synthesis via aldehydes and ketones precondensation. Herein, we discovered a [1 + 2 + 1 + 2] four-component domino cyclization reaction, a novel concept in 4CRs with commercially available ketones and aldehydes, which by initially combining aldehydes and ketones with Meldrum's acid and ammonium acetate (NHOAc), respectively, they give dihydropyridones (>110 examples). This transformation features inexpensive additives and readily available starting materials, making it appropriate for rapid access to relevant pharmaceutical molecules containing dihydropyridinone-derived heterocycles.
View Article and Find Full Text PDFOrg Lett
October 2024
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
Herein, we evolve a base-promoted synthesis of 2-chromen-2-one and chromeno[2,3-]pyrrole scaffolds via (4 + 2) annulation of α-alkylidene succinimides with 2-hydroxyphenyl-substituted -quinone methides (-QMs). Extremely selective and switchable cyclizations were obtained by modifying the base. This metal-free protocol is highlighted by its mild reaction conditions and broad substrate scope, and the viability of the existing protocol was additionally illustrated by gram-scale synthesis and further modification.
View Article and Find Full Text PDFOrg Lett
September 2024
Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R. China.
A novel and unique approach for the construction of polysubstituted pyrimido[4,5-]indoles from 2-(indol-3-yl)naphthoquinones and benzamidines is described. Our strategy, promoted by an inorganic base, involves the ring opening and recyclization of naphthoquinone and produces three nitrogen heterocyclic rings via multiple C-N bond formations in one pot under transition-metal-free conditions.
View Article and Find Full Text PDFOrg Biomol Chem
September 2024
Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China.
Aromatic 1,2,4-diazaphospholes featuring distinct hybrid-mode nitrogen atoms (N(λσ), N(λσ)) and low-valent phosphorus atoms (λσ) exhibited the characteristic of serving as unique hybrid ligands. This study presented a one-pot reaction involving the base-promoted stepwise cyclization of hydrazonoyl chlorides and [BuN][P(SiCl)] to yield 1,2,4-diazaphospholes, providing an effective method for synthesizing such compounds.
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