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1.
A number of 2,5-bis(aryl- and alkyloxycarbonyloxymethylene)-3,6-bis(aryl- and alkoxycarbonyloxy)-1,4-dioxanes 5a-d have been prepared by the reaction of glyceraldehyde with aryl and alkyl chloroformates. Bis aryl carbonates were also formed under certain conditions in this reaction. Nuclear magnetic resonance analysis of 5c indicated that it existed in a chair conformation with all the substituents in an equatorial position.  相似文献   

2.
2-Phenoxy- and 2-dialkylamino-2-oxa-1,3,2-oxathiaphospholanes react with PCl5 with ring opening and formation of the corresponding acid chlorides of thiophosphoric acid. Under analogous conditions, 2-phenoxy-2-oxo-1,3,2-oxathiaphosphorinanes do not react with PCl5, while acid chlorides of thiophosphoric acid are formed in low yield along with other products in the reaction of 2-dialkylamino-2-oxo-1,3,2-oxthiaphosphorinanes with PCl5.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2676–2678, November, 1992.  相似文献   

3.
The reaction of 2-alkyl-4,6-bistrichloromethyl-symm-triazines containing higher alkyl groups with ammonia or aliphatic amines results, depending on the reaction conditions, in the replacement of one or both trichloromethyl groups. On heating these symm-triazines with aqueous ammonia or dimethylamine, 2-oxo-4-amino-6-alkyl-1(3)H-symm-triazines are obtained.For communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1557–1563, November, 1985.  相似文献   

4.
《Tetrahedron letters》1987,28(23):2599-2602
Two novel alternative procedures for the synthesis of 1,4-alkanediols were described by involving the reactions of (dichloromethyl)lithium with some 1,2-oxaborolane derivatives readily obtainable from allyl alcohol.  相似文献   

5.
Fluorine-containing alkyl 2-cyano-3-oxocarboxylates were synthesized for the first time by the reaction of ethyl cyanoacetate with fluorine-substituted carboxylic acid halides or alkyl carboxylates. The reactions with hydrazine hydrate, phenylhydrazine, ando-phenylenediamine give hydrazinium (ammonium) enolates or products of acid decomposition. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1961–1965, October, 1999.  相似文献   

6.
3-Oxo-2,3-dihydrobenzofuran reacted with ethyl 2-cyano-3-ethoxypropenoate, methyl 2-cyano-3-methoxy-propenoate affording compounds 3 (2-(2-cyano-2-alkoxycarbonylvinyl)-3-hydroxybenzofuran) obtained as a mixture of Z + E isomers. Methyl 2-methoxycarbonyl-3-methoxypropenoate gave compound 4 . Malonic compounds added on 2-dimethylaminomethylene-3-oxo-2,3-dihydrobenzofuran 6 for giving compound 3 or 2-oxo-3-methoxycarbonyl-2H-pyrano[3,2-b]benzofuran 8 . Compound 8 was also obtained by heating compound 4 in xylene.  相似文献   

7.
8.
It is demonstrated with the help of1H and13C NMR spectroscopy and GLC that the formation of the stereoisomers of 2-alkyl-4,5-dimethyl-1,3,2-dioxaborinanes from 2-methyl-1,3-butanediol and acyclic boric acid esters occurs stereospecifically. This conclusion was confirmed by calculations of the optimal geometries and relative energies of the molecules of thecis-andtrans-isomers of model 4,5-dimethyl-1,3,2-dioxaborinanes and the proposed intermediate with a tetravalent boron atom using the method of molecular mechanics.A. V. Bogatskii Physicochemical Institute, National Academy of Sciences of Ukraine, Odessa 270080, Ukraine. Institute of Organic Chemistry, Ufa Science Center, Russian Academy of Science, Ufa 450054, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 400–404, March, 1998.  相似文献   

9.
Summary A study was made of the condensation of benzaldehyde and acetaldehyde acetals with alkyl 2-bromovinyl ethers, as a result of which bromo ethoxy acetals of general formula RCH(OC2H5)CHBrCH(OR)2 (R=C6H5 and CH3) were formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 282–285, February, 1965  相似文献   

10.
11.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 271–272, February, 1993.  相似文献   

12.
The reactions of 2-dimethylamino-, 2-methoxy-, 2-chloro-4,5-dimethyl-1,3,2-dioxaphos-pholanes with 4-thiocyanato-2-butanol in all cases yield 2-(1-methyl-3-thiocyanatopropoxy)-4,5-dimethyl-1,3,2-dioxaphospholane. The latter reacts with elemental sulfur to form the corresponding thiophosphate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2130–2131, December, 1993.  相似文献   

13.
Reactions of alkyl 3-amino-5-aryl-2-benzoyl-2-oxopent-2-enoates with hydrazine were accompanied by debenzoylation and isomerization to give 3-amino-5-aryl-5-oxopent-3-enohydrazides, which underwent cyclization in the presence of an excess of hydrazine into 5(3)-arylpyrazol-3(5)-ylacetohydrazides. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1175–1177, July, 2006.  相似文献   

14.
15.
Quantum chemical study of conformational isomerization of 2-methyl-5-alkyl- and 5-aryl-1,3,2-dioxaborinanes using RHF/6-31G(d) method led to the conclusion that the equilibrium between equatorial and axial sofa conformers is shifted to the latter form. Based on the experimental and theoretically calculated vicinal coupling constants J HH the quantitative conformational composition and the values of ΔG 0 for substituents at the C5 ring atom were established.  相似文献   

16.
17.
18.
Alkyl 2-benzylidene-2-polyfluoroacylacetates react with urea and thiourea to yield 5-ethoxycarbonyl-4-fluoroalkyl-4-hydroxy-6-phenylhexahydropyrimidin-2-ones and -2-thiones and with guanidine sulfate to form 2-amino-5-ethoxycarbonyl-4-fluoroalkyl-6-phenyl-1,6-dihydropyrimidines and 3,6-diethoxycarbonyl-2,7-difluoroalkyl-4,5-diphenyl-4,5-dihydro-1H-pyrido[1,2-a]pyrimidines, and they react with phenylhydrazine to afford 4-alkoxycarbonyl-3-fluoroalkyl-3-hydroxy-1,5-diphenylpyrazolidines. Hydrazine hydrate catalyzes the formation of 3,5-diethoxycarbonyl-2,6-difluoroalkyl-2,6-dihydroxy-4-phenyltetrahydropyrans. When treated with anhydrous hydrazine and o-phenylenediamine, these esters cleave to form the products of condensation of fluoroacyl ester and benzaldehyde with diamines.  相似文献   

19.
20.
Five-membered cyclic esters of phosphoric acid of the general formula: ? CH2CH(R)OP(O)-(OR′)O? polymerize readily to solid, soluble polymers of high molecular weight without any rearrangement known for various tri- and pentavalent organophosphorus monomers. 1H-, 13C-, and 31P-NMR spectra of polymers confirmed their linear structure: where R is H, with R′ = CH3, C2H5, n-C3H7, i-C3H7; n-C4H9, CCl3CH2, or C6H5, or R is CH2Cl and R′ is C2H5. The use of n-C4H9Li, (C5H5)2Mg, or (i-C4H9)3Al as initiators leads to polymers with M n = 104–105.  相似文献   

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