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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Chemical Methodologies
- نوع مقاله: Journal Article
- کلمات کلیدی: Ultrasonic and microwave irradiation,Benzamide/ SO2Cl2,Rate accelerations
- چکیده:
- چکیده انگلیسی: Benzamide/ Sulfuryl Chloride (SO2Cl2) reagent has been developed as a Vilsmeier- Haack(VH) reagent for benzoylation of aromatic compounds by using the conventional and ultrasonic sonication (US), and microwave (MW) conditions. Benzoylation is much more competent and faster than the analogous VH ((Benzamide/ POCl3) or (Benzamide/ SOCl2)) reagents and afforded benzoyl derivatives in good yields. Reaction times are moderately less than those observed with [Benzamide/ POCl3] and (Benzamide/ SOCl2) reagents. Reaction times are far less in microwave assisted (MWAR) reactions than ultrasonically assisted (USAS) reactions , which in turn are less than the conventional method with a decreasing trend: MWAR (seconds) << Sonication (minutes) << conventional (hrs). The highly remarkable rate accelerations in MW assisted reactions are attributed to the bulk activation of the molecules; while US assisted reactions could be accounted for cavitation effects.
- انتشار مقاله: 10-06-1396
- نویسندگان: Marri Venkateswarlu,Mukka Satish Kumar,Chinna Rajanna Kamatala,Purugula Venkanna,Pondichery Kuppuswamy Saiprakash
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Journal of Green Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Si-supported BrØnsted acids,Green reuasble catalysts,NaHSO3,Sulfonation,aromatic compounds
- چکیده:
- چکیده انگلیسی: A green protocol is described for sulfonation of aromatic compounds that has been accomplished using sodium bisulfite (NaHSO3) in the presence of reusable green heterogeneous SiO2/HClO4 and SiO2/KHSO4 (Silica-supported HClO4 and KHSO4 catalysts) under conventional and solvent-free microwave irradiation. The reactions afforded very good yields of products within 3 to 5 hour under conventional conditions. However, the reaction times in microwave-assisted protocol are drastically reduced to 3 to 5 minutes (from 3 to 5 hour under conventional conditions) followed by increasing product yields. Moreover, the developed silica-supported catalysts could be recycled for at least three to four times.
- انتشار مقاله: 25-05-1396
- نویسندگان: Touheeth Fatima,Yeike Hemanth Sriram,Mukka Satish Kumar,Marri Venkateswarlu,Chinna Rajanna Kamatala
- مشاهده