An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byprod...An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byproduct was recovered in high yield by simple filtration. Some aromatic acids have been transformed into the corresponding acid chlorides in good yields by employing the isolated VH. Treatment of primary or secondary alcohols with VH gave alkyl formates or alkyl chlorides by depending on the reaction conditions.展开更多
Nitration of aromatic Compounds is triggered by Vilsmeier-Haack reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of KNO3 or NaNO2 under conventional and non-conventional conditions. The reactions af- forded correspo...Nitration of aromatic Compounds is triggered by Vilsmeier-Haack reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of KNO3 or NaNO2 under conventional and non-conventional conditions. The reactions af- forded corresponding Nitro derivatives in very good yield with high regioselectivity. The results obtained in non-conventional methods (Micro wave irradiation, Grinding, Sonication) are comparable with those ob- tained under conventional conditions, but the reaction times of former conditions are substantially shorter than that of the latter.展开更多
Sulfonation of aromatic compounds (Phenols, Anilines) is triggered by Vilsmeier Haack (VH) reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of NaHSO3 under Sonication and conventional stirred conditions at room temp...Sulfonation of aromatic compounds (Phenols, Anilines) is triggered by Vilsmeier Haack (VH) reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of NaHSO3 under Sonication and conventional stirred conditions at room temperature. The reactions afforded corresponding Sulfonic acid derivatives in very good yields. The results obtained under Sonication were enhanced when compared with the yields of the conventional method.展开更多
Acetylation and benzoylation reactions of certain aromatic aldehydes, ketones with Vilsmeier-Haack Re- agents using Acetamide and Oxychloride (SOCl2 or POCl3) under conventional (thermal) and non conven- tional [micro...Acetylation and benzoylation reactions of certain aromatic aldehydes, ketones with Vilsmeier-Haack Re- agents using Acetamide and Oxychloride (SOCl2 or POCl3) under conventional (thermal) and non conven- tional [microwave irradiated (MIR), ultrasonic assisted and solvent free mortar pestle (grinding)] conditions. Reactions afforded good to excellent yields of products with both the VH reagents, reaction times were fairly less in the case of [amide/POCl3] than those of [amide/SOCl2] reagent. Reactions are dramatically acceler- ated in under sonicated and microwave irradiations with a trend: MIR (few seconds) >> Sonication (minutes) > Grinding (min) >> thermal (several hrs).展开更多
文摘An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byproduct was recovered in high yield by simple filtration. Some aromatic acids have been transformed into the corresponding acid chlorides in good yields by employing the isolated VH. Treatment of primary or secondary alcohols with VH gave alkyl formates or alkyl chlorides by depending on the reaction conditions.
文摘Nitration of aromatic Compounds is triggered by Vilsmeier-Haack reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of KNO3 or NaNO2 under conventional and non-conventional conditions. The reactions af- forded corresponding Nitro derivatives in very good yield with high regioselectivity. The results obtained in non-conventional methods (Micro wave irradiation, Grinding, Sonication) are comparable with those ob- tained under conventional conditions, but the reaction times of former conditions are substantially shorter than that of the latter.
文摘Sulfonation of aromatic compounds (Phenols, Anilines) is triggered by Vilsmeier Haack (VH) reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of NaHSO3 under Sonication and conventional stirred conditions at room temperature. The reactions afforded corresponding Sulfonic acid derivatives in very good yields. The results obtained under Sonication were enhanced when compared with the yields of the conventional method.
基金Project supported by the National Natural Science Foundation of China(No.20572079)the Natural Science Foundation of Zhejiang Province(No.Y407079)the Foundation of Science and Technology Department of Zhejiang Province(No.2007C21116).
文摘Acetylation and benzoylation reactions of certain aromatic aldehydes, ketones with Vilsmeier-Haack Re- agents using Acetamide and Oxychloride (SOCl2 or POCl3) under conventional (thermal) and non conven- tional [microwave irradiated (MIR), ultrasonic assisted and solvent free mortar pestle (grinding)] conditions. Reactions afforded good to excellent yields of products with both the VH reagents, reaction times were fairly less in the case of [amide/POCl3] than those of [amide/SOCl2] reagent. Reactions are dramatically acceler- ated in under sonicated and microwave irradiations with a trend: MIR (few seconds) >> Sonication (minutes) > Grinding (min) >> thermal (several hrs).