In the presence of KF·2H2O, furoylmethyltriphenylarsonium bromide (1a) or thienoylmethyltriphenylarsonium bromide (1b) reacted with 2-[(un)substituted benzylidene]malononitrile (2) in chloroform at room t...In the presence of KF·2H2O, furoylmethyltriphenylarsonium bromide (1a) or thienoylmethyltriphenylarsonium bromide (1b) reacted with 2-[(un)substituted benzylidene]malononitrile (2) in chloroform at room temperature to give trans-3,3-dicyano-1-furoyl-2-[(un)substituted phenyl]cyclopropane (3a) or trans-3,3-dicyano-1-thienoyl-2- [(un)substituted phenyl]cyclopropane (3b) respectively in good yield with high stereoselectivity. The structures of product 3 were confirmed by IR, MS, 1^H NMR, 1^H-1^H COSY and microanalysis. The relative configuration of product 3 was determined by 1^H-1^H NOESY technique. The mechanism for the formation of product 3 was also proposed.展开更多
An easy and efficient method for the synthesis of multisubstituted cyclopropane derivatives from electron-deficicent alkenes with 2-bromo-1,3-propanedione compounds was described.For this method,ethylα-cyanocinnamate...An easy and efficient method for the synthesis of multisubstituted cyclopropane derivatives from electron-deficicent alkenes with 2-bromo-1,3-propanedione compounds was described.For this method,ethylα-cyanocinnamate derivatives 1 andβ,β-dicyanostyrene derivatives 4 can all smoothly reacted with 2-bromo-1,3-propanedione compounds 2 to afford the corresponding multisubstituted cyclopropane derivatives 3 and 5 in good to excellent yields(up to 100%)promoted by anhydrous K3PO4 in DMF at room temperature,respectively.A possible mechanism of this reaction was proposed.Structures of all the products were confirmed by ^1H NMR,^13C NMR and HRMS.展开更多
Phenylglycine 1 as a representative of natural resourceful a-amino acid was modified by reduction and protection of functional group to afford the amino alcohol as a chiral building block 3. A new chiral compound, the...Phenylglycine 1 as a representative of natural resourceful a-amino acid was modified by reduction and protection of functional group to afford the amino alcohol as a chiral building block 3. A new chiral compound, the chiral building block/spiro-cyclopropane derivative containing four stereogenic centers, compound 7, has been obtained in 52% yield with de≥98% via the tandem double Michael addition/internal nucleophilic substitution under mild condition of 5-l-menthyloxy-3-bromo-2-(5H)-furanone 4 with the nucleophilic reagent, the amino alcohol 3. The new chiral compound 7 is identified on the basis of its analytical data and spectroscopic data, such as UV, IR, 1H NMR, 13C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes 7 was established by X-ray crystallography. This result can provide new route and method for the introduction of chiral building block and the important synthetic strategy in synthesis of some complex molecules containing展开更多
The fluorine-containing trans-l,2-cyclopropane derivatives 4ba--4dd were synthesized from the fluorine-containing electron-deficient alkenes 3a--3d with semistabilized arsonium ylides 2b--2d, in biphasic system of dic...The fluorine-containing trans-l,2-cyclopropane derivatives 4ba--4dd were synthesized from the fluorine-containing electron-deficient alkenes 3a--3d with semistabilized arsonium ylides 2b--2d, in biphasic system of dichloromethane-50% aqueous sodium hydroxide, generated in situ from the corresponding arsonium salts 1b-1d at room temperature in good yields with high stereoselectivity. The structure of fluorine-containing trans-1,2-cyclopropane derivatives were also studied.展开更多
The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a...The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex展开更多
基金Project supported by the National Natural Science Foundation of China (No. 20472047), the Natural Science Foundation of Shanghai (No. 04ZR14060) and the Education Commission of Shanghai Municipality (Nos. 05AX12 and B.99-0303-06-034).
文摘In the presence of KF·2H2O, furoylmethyltriphenylarsonium bromide (1a) or thienoylmethyltriphenylarsonium bromide (1b) reacted with 2-[(un)substituted benzylidene]malononitrile (2) in chloroform at room temperature to give trans-3,3-dicyano-1-furoyl-2-[(un)substituted phenyl]cyclopropane (3a) or trans-3,3-dicyano-1-thienoyl-2- [(un)substituted phenyl]cyclopropane (3b) respectively in good yield with high stereoselectivity. The structures of product 3 were confirmed by IR, MS, 1^H NMR, 1^H-1^H COSY and microanalysis. The relative configuration of product 3 was determined by 1^H-1^H NOESY technique. The mechanism for the formation of product 3 was also proposed.
基金Supported by the Natural Science Foundation of Shaanxi Province,China(No.2009JM2001)the Innovation Foundation of Postgraduate Cultivation of Shaanxi Normal University,China(No.2008CXB009).
文摘An easy and efficient method for the synthesis of multisubstituted cyclopropane derivatives from electron-deficicent alkenes with 2-bromo-1,3-propanedione compounds was described.For this method,ethylα-cyanocinnamate derivatives 1 andβ,β-dicyanostyrene derivatives 4 can all smoothly reacted with 2-bromo-1,3-propanedione compounds 2 to afford the corresponding multisubstituted cyclopropane derivatives 3 and 5 in good to excellent yields(up to 100%)promoted by anhydrous K3PO4 in DMF at room temperature,respectively.A possible mechanism of this reaction was proposed.Structures of all the products were confirmed by ^1H NMR,^13C NMR and HRMS.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 29672004).
文摘Phenylglycine 1 as a representative of natural resourceful a-amino acid was modified by reduction and protection of functional group to afford the amino alcohol as a chiral building block 3. A new chiral compound, the chiral building block/spiro-cyclopropane derivative containing four stereogenic centers, compound 7, has been obtained in 52% yield with de≥98% via the tandem double Michael addition/internal nucleophilic substitution under mild condition of 5-l-menthyloxy-3-bromo-2-(5H)-furanone 4 with the nucleophilic reagent, the amino alcohol 3. The new chiral compound 7 is identified on the basis of its analytical data and spectroscopic data, such as UV, IR, 1H NMR, 13C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes 7 was established by X-ray crystallography. This result can provide new route and method for the introduction of chiral building block and the important synthetic strategy in synthesis of some complex molecules containing
基金Project supported by the the National Natural Science Foundation of China (Nos. 20872086 and 20872088), and the Project of Shanghai Municipal Education Commission (Nos. 09YZ19 and J50102).
文摘The fluorine-containing trans-l,2-cyclopropane derivatives 4ba--4dd were synthesized from the fluorine-containing electron-deficient alkenes 3a--3d with semistabilized arsonium ylides 2b--2d, in biphasic system of dichloromethane-50% aqueous sodium hydroxide, generated in situ from the corresponding arsonium salts 1b-1d at room temperature in good yields with high stereoselectivity. The structure of fluorine-containing trans-1,2-cyclopropane derivatives were also studied.
文摘The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex