Liquid crystals containing phenylpyrimidine units are the fascination condensed state of soft matter with unique electrical, optical and mechanical properties. In this paper, a novel and efficient route was reported f...Liquid crystals containing phenylpyrimidine units are the fascination condensed state of soft matter with unique electrical, optical and mechanical properties. In this paper, a novel and efficient route was reported for the synthesis of N-（3-（dimethylamino）-2-（4-ethoxyphenyl）allylidene）-N-methylmethanaminium perchlorate by the WillgerodtKindler reaction, which can be further applied to prepare liquid crystals containing phenylpyrimidine units. The product was confirmed by JHNMR, MS, FT-IR and elemental analysis. The experimental conditions of the Willgerodt-Kindler reaction were also studied and the results show that the yield of p-ethoxyphenyl-acetic acid increased remarkably with a reaction time up to 60 rain, then decreased due to carbonization. On the other hand, the yield was also influenced by microwave power. It increased from 20.6 % to 78.8 % with a rise in the microwave power from 250 W to 450 W, but the product was carbonized at 640 W.展开更多
A simple and regioselective synthesis of 2-chloro-3-formyl-l,8-naphthyridine （1） through V ilsmeier-Haack cyclization of N-（pyridine-2-yl） acetamide has been reported. The reaction of compound （1） with sodium su...A simple and regioselective synthesis of 2-chloro-3-formyl-l,8-naphthyridine （1） through V ilsmeier-Haack cyclization of N-（pyridine-2-yl） acetamide has been reported. The reaction of compound （1） with sodium sulphide gives thione （2） and the reaction of compound （1） with Na2S/DMF followed by reaction with alkyl halide in one pot afforded thioether （3 and 4）. New naphthyridone （5） was synthesized from the action of acetic acid and POCI3 in compound （1）. The condensation of compounds （1 and 8） with hydroxylamine and aniline leads to the formation of compounds （6, 7 and 9）. The 2-chloro-3-formyl-l,8-naphthyridine was treated with sodium azide underwent cyclization to afford tetrazolo （l,5-a） （l,8-naphthyridine-4-carbaldehyde （8）. The azitidinone （10 and 12） and thioazolidinone （11 and 13） were synthesized from shift base intermediates by using chloroacetyl chloride and thioglycolic acid. The formyl group in compound （1） is subjected to cyano （14） and 3-alkoxycarbonyl （15）, respectively. The ester （15） was treated with hydrazine hydrate in ethanol to give acid hydrazide （16） then converted to thio semicarbazide （17） by their reaction with ammonium thiocyanate. New thiadiazolo （18）, triazolo （19） and oxadiazolo （20） have been prepared. The structures of synthesized compounds have been confirmed by suitable spectroscopic techniques such as IR （infrared spectrometry） and ^1H NMR （proton nuclear magnetic resonance）.展开更多
文摘Liquid crystals containing phenylpyrimidine units are the fascination condensed state of soft matter with unique electrical, optical and mechanical properties. In this paper, a novel and efficient route was reported for the synthesis of N-（3-（dimethylamino）-2-（4-ethoxyphenyl）allylidene）-N-methylmethanaminium perchlorate by the WillgerodtKindler reaction, which can be further applied to prepare liquid crystals containing phenylpyrimidine units. The product was confirmed by JHNMR, MS, FT-IR and elemental analysis. The experimental conditions of the Willgerodt-Kindler reaction were also studied and the results show that the yield of p-ethoxyphenyl-acetic acid increased remarkably with a reaction time up to 60 rain, then decreased due to carbonization. On the other hand, the yield was also influenced by microwave power. It increased from 20.6 % to 78.8 % with a rise in the microwave power from 250 W to 450 W, but the product was carbonized at 640 W.
文摘A simple and regioselective synthesis of 2-chloro-3-formyl-l,8-naphthyridine （1） through V ilsmeier-Haack cyclization of N-（pyridine-2-yl） acetamide has been reported. The reaction of compound （1） with sodium sulphide gives thione （2） and the reaction of compound （1） with Na2S/DMF followed by reaction with alkyl halide in one pot afforded thioether （3 and 4）. New naphthyridone （5） was synthesized from the action of acetic acid and POCI3 in compound （1）. The condensation of compounds （1 and 8） with hydroxylamine and aniline leads to the formation of compounds （6, 7 and 9）. The 2-chloro-3-formyl-l,8-naphthyridine was treated with sodium azide underwent cyclization to afford tetrazolo （l,5-a） （l,8-naphthyridine-4-carbaldehyde （8）. The azitidinone （10 and 12） and thioazolidinone （11 and 13） were synthesized from shift base intermediates by using chloroacetyl chloride and thioglycolic acid. The formyl group in compound （1） is subjected to cyano （14） and 3-alkoxycarbonyl （15）, respectively. The ester （15） was treated with hydrazine hydrate in ethanol to give acid hydrazide （16） then converted to thio semicarbazide （17） by their reaction with ammonium thiocyanate. New thiadiazolo （18）, triazolo （19） and oxadiazolo （20） have been prepared. The structures of synthesized compounds have been confirmed by suitable spectroscopic techniques such as IR （infrared spectrometry） and ^1H NMR （proton nuclear magnetic resonance）.
