Expeditious,Nano-BF3 · SiO2-Catalyzed Michaelis–Arbuzov Reaction in an Ionic Liquid: Synthesis of Privileged Aryl/Heterocyclic Phosphonates

An expeditious, simple, and green method was developed for the synthesis of privileged aryl/heterocyclicphosphonates, 8(a–c) to 13(a–c) through Michaelis–Arbuzov reaction of aryl/heterocyclic halides (Br), 1–6, and trialkylphosphites, 7(a–c), in room-temperature ionic liquid [bbim]Br using heterogeneous Lewis catalyst, nano-silica-supported boron trifluoride (BF₃-SiO₂). The advantages of this protocol are simplicity, good yield of the products, less reaction time (20–38 min), mild reaction conditions, easy workup, and reusability of the catalyst and ionic liquid. It is demonstrated that nano-BF₃-SiO₂ is a recoverable and easy accessible catalyst for the formation of C(sp²)-P bond in an ionic liquid.     

New substituted 2-aminomethyl-2-oxo-2λ5-perhydro-[1,3,2]oxazaphospholo [3,4-a]pyridine: Design,synthesis and antimicrobial activity

The synthesis of a new series of P-heterocyclic compounds, substituted 2-aminomethyl-2-oxo-2λ⁵-perhydro-[1,3,2]oxazaphospholo[3,4-a]pyridine derivatives 8(a-j), was accomplished. A key intermediate, 2-(chloromethyl)-2-oxo-2λ⁵-perhydro-[1,3,2]oxazaphospholo[3,4-a]pyridine (6) was primarily synthesized by the condensation of (±)-2-piperidinemethanol (4) and chloromethylphosphonic dichloride (5); subsequently, it was treated with various heterocyclic amines/benzylamines/aminoacid esters, 7(a-j) to obtain the desired products. The structures of the newly synthesized compounds were elucidated by ¹H, ¹³C, and ³¹P NMR spectroscopy, mass spectra and elemental analyses. The biological potency of title products was investigated by screening in vitro antimicrobial activity. The bio-screening data revealed that most of the synthesized derivatives showed potent growth of inhibition against fungi while compared with bacteria. Particularly, compounds 8c and 8i against bacterial strains, and 8a and 8f against fungi exhibited promising activity.     

Sulfonamides and carbamates of 3-fluoro-4-morpholinoaniline (linezolid intermediate): synthesis,antimicrobial activity and molecular docking study

Research on Chemical Intermediates - The precursor compound 3-fluoro-4-morpholinoaniline (7) is an important intermediate of the antibiotic drug linezolid and was synthesized initially by the...     

An efficient microwave-promoted three-component synthesis of thiazolo[3,2-a]pyrimidines catalyzed by SiO2–ZnBr2 and antimicrobial activity evaluation

Chemistry of Heterocyclic Compounds - 2,5-substituted-6-(4-nitrophenyl)-5H-thiazolo[3,2-a]pyrimidin-7-amines. This method, optimized under microwave conditions, was highly efficient and...     

Facile new industrial process for synthesis of teneligliptin through new intermediates and its optimization with control of impurities

Research on Chemical Intermediates - The present study is related to a commercially practicable new synthetic process for production of teneligliptin hydrobromide hydrate (1), a dipeptidyl...     

CeCl3·7H2O-SiO2： Catalyst promoted microwave assisted neat synthesis, antifungal and antioxidant activities of α-diaminophosphonates

CeCl₃·7H₂O supported on silica（CeCl₃·7H₂O-SiO₂） is used as a heterogeneous,efficient and recyclable catalyst for a three component one-pot reaction of an amine,aldehydes and diethyl phosphite to synthesizeα-diaminophosphonate derivatives under microwave irradiation exploiting neat reaction conditions.Tenα-diaminophosphonates（6a-j） of 4,4’-sulfonyldianiline（Dapsone）（3） were synthesized and structural elucidation was confirmed by spectral data.Antifungal and antioxidant activities were evaluated include minimum inhibitory concentrations and IC₅₀ values,respectively of the titled compounds.Compounds 6h,6i exhibited promising antioxidant activity at lower IC₅₀ values 53.7μg/mL, 53.2μg/mL,respectively as compared with standard IC₅₀ value 51.6μg/mL.