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1.
The cyclopropanation reaction of α,α′-bis (substitutedbenzylidene)cycloalkanones with telluronium ylides was studied. The products were proved to be the derivative of dispiro[2, 1, 2, 2]nonane-4-one and dispiro[2, 1, 2, 3]decane-4-one. 相似文献
2.
Pyrolysis of 3-allylcyclopentanones affords -6-substituted bicyclo[2.2.1]heptan-2-ones. 相似文献
3.
Bicyclo[4.2.0]octa-1,3,5-trien-3-ol (2) has been synthesized in good yield via a Baeyer-Villiger reaction of the corresponding aldehyde 5 with permonophosphoric acid. 相似文献
4.
Acid-promoted cyclopropane cleavage reactions have been employed with great success for the generation of angular methyl groups.2 Sims has shown that the regioselectivity of such reactions may be influenced by acid strength.2d We now report a case in which steric factors appear to direct the cleavage pathway. 相似文献
5.
A highly efficient Rhodium(III)-catalyzed annulative coupling was developed for generating bicyclo[4.1.0] heptan-2-ones from sulfoxonium ylides and allyl acetates under mild conditions. This cascade reaction is versatile to construct cyclopropanes, and the starting materials are stable and easily obtainable. 相似文献
6.
7.
A. Alan Pinkerton Dieter Schwarzenbach Jean-Luc Birbaum Pierre-Alain Carrupt Luis Schwager Pierre Vogel 《Helvetica chimica acta》1984,67(4):1136-1153
The crystal structures of (1R,4R,5S,8S)-9,10-dimethylidentricyclo[6.2.1.02,7]undec2(7)-ene-4,5-dicarboxylic anhydride ( 3 ), (1R,4R,5S,8S)11-isopropylidene-9,10-dimethylidenetricyclo[6.2.1.m2,7]undec-2(7)-ene-4,5-dicarboxylic anhydride ( 6 ), (1R,4R,5S8S)-9,10-dimethylidenetricyclo[6.2.2.02,7]dodec-2(7)-ene-4,5-dicarboxylic anhydride ( 9 ), (1R4R5S8S)-TRICYCLO[6.2.2.02,7]dodeca-2(7), 9-diene-4,5-dicarboxylic anhydride ( 12 ) and (4R,5S)-tricyclo[6.1.1.02.7]dec-2(7)-ene-4,5-dicarboxylic acid ( 16 ) were established by X-ray diffraction. The alkyl substituents onto the endocyclic bicyclo[2.2.1]hept-2-ene double bond deviate from the C(1), C(2), C(3), C(4), plane by 13.5°4 in 3 and by 13.9° in 6 , leaning toward the endo-face. No such out-of-plane deformations were observed with the bicyclo[2.2.2]oct-2-ene derivatives 9 and 12 . The exocyclic s-cis-butadiene moieties in 3, 6 and 9 do not deviate significantly from planarity. The deviation from planarity of the double bond n bicyclo[2.2.1]hept-2-ene derivatives and planarity in bicyclo[2.2.2]oct-2-ene analogues is shown to be general by analysis of all known structures in the Cambridge Crystallographic Data File. The non-planarity of the bicyclo[2.2.1]hept-2-ene double bond cannot be attributed only to bond-angle deformations which would favour rehybridizatoin of the olefinic C-atoms since the double bond in the more strained bicyclo[2.1.1]hex-2-ene drivative 16 deviates from planarity by less than 4°. 相似文献
8.
Gerald Lange Marc E. Savard Thammaiah Viswanatha Gary I. Dmitrienko 《Tetrahedron letters》1985,26(15):1791-1794
3-Carboalkoxy-2,3-dihydrothiophenes, available by Birch reduction of thiophene-3-carboxylic acid or more efficiently by deconjugation of 2,5-dihydrothiophene-3-carboxylic acid by reaction with ethyl chloroformate and triethylamine, undergo cycloaddition reactions with dichloroketene leading to 4-carboxy-7,7-dichloro-2-thiabicyclo[3.2.0]heptan-6-ones which are of interest as potential β-lactamase inhibitors. 相似文献
9.
Several novel triacetal trioxa-cage compounds 11a-11g, 13, 15, 17 and 19 are synthesized in a short sequence. Ozonolysis of bicyclo[2.2.1]heptenes 4a-4c, 8a-8c, 10a, 10b and 14 in dichloromethane at ?78 °C followed by reduction with dimethyl sulfide gave triacetal oxa-cages 11a-11g, 13 and 15 in moderate yields, respectively. Ozonolysis of bicyclo[2.2.2]octenes 16 and 18 under the same reaction conditions gave triacetal oxa-cages 17 and 19 in moderate yields, respectively. 相似文献
10.
A short synthesis of 2-formylbicyclo[3.1.1]-hept-2-ene, suitable for multigram preparations, is presented. 相似文献
11.
Interest in the synthetic potential of rearrangement reactions of fused-ring cyclobutanediols1,2 has led us to develop a general method for the synthesis of bicyclo[n.2.0] alkanediols in which the hydroxyl group are located on adjacent carbon atoms at the bridgehead and in the cyclobutane ring (e.g. 1). We report here the application of our new synthetic method to the synthesis of bicyclo [4.2.0] octane-1,8-diol (2) and bicyclo[3.2.0]-heptane-1,7-diol (3). 相似文献
12.
The bicyclo[3.3.0] octene system has been synthesised from the readily available starting material 2-methyl-cyclohexane-1,3-dione, utilizing the base catalysed oxy-Cope rearrangement as a key step. 相似文献
13.
Allylation of the C-2 enolate of the bicyclo[3.3.1]nonenedione 1 proceeds with an unusual acyl migration to yield the C-allyl ester 5 of the rearranged bicyclo[4.2.1]nonenedione system. 相似文献
14.
Synthesis of the pure, bicyclic olefines Bicyclo[4.2.1]non-2-ene, Bicyclo[4.2.1]non-3-ene and Bicyclo[4.2.1]non-7-ene The synthesis of the olefines bicyclo[4.2.1]non-2-ene ( 3 ), bicyclo[4.2.1]non-3-ene ( 4 ) and bicyclo[4.2.1]non-7-ene ( 5 ) of high ‘certified’ purity from one common precursor ( 7 ) is described. 相似文献
15.
Mishra M. Nizam A. Jomon K. J. Tadaparthi K. 《Russian Journal of Organic Chemistry》2019,55(12):1925-1928
Russian Journal of Organic Chemistry - Pyrano[2,3-c]pyrazole derivatives have been synthesized through a one-pot multicomponent condensation of various aldehydes, dialdehydes, and ketones with... 相似文献
16.
Isothiocyanate 2, obtained from aza-Wittig reaction of iminophosphorane 1 with CS2, reacted with amine to give 2-thioxo-2,3,5,6,7,8-hexahydrobenzothieno[2,3-d]pyrimidin-4(1H)-ones 4 in the presence of sodium ethoxide. S-Alkylation of 4 produced 2-alkylthio-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidin-4(3H)-ones 5 in good yields. 相似文献
17.
Bicyclo[3.2.1]oct-6-en-2-ols 6 are shown to undergo [1,3] sigmatropic shift to afford 8-endo-hydroxy-bicyclo[3.3.0]oct-2-en-4-ones 8 under the influence of potassium hydride. 相似文献
18.
A shorter and significantly higher-yield procedure for the preparation of bicyclo[3.3.3]undecane (manxane) is reported. 相似文献
19.
20.
Convenient syntheses of the epimeric 3-hydroxy-2α-carb-oxybicyclo[3.3.0]octane-4α,6α-carbolactones are described which commence from the readily available cyclopentadienone dimer. 相似文献