New Chiral Diamines of the Dioxolane Series: (+)-(4S,5S)-2,2-Dimethyl-4,5-bis(diphenylaminomethyl)- 1,3-dioxolane and (+)-(4S,5S)-2,2-Dimethyl-4,5-bis(methyl- aminomethyl)-1,3-dioxolane

The reaction of sodium diphenylamide with 2,2-dimethyl-4,5-bis(tosyloxymethyl)-1,3-dioxolane gave (+)-(4S,5S)-2,2-dimethyl-4,5-bis(diphenylaminomethyl)-1,3-dioxolane, which was brought into complex formation with cobalt chloride. Treatment of 2,2-dimethyl-4,5-bis(tosyloxymethyl)-1,3-dioxolane with sodium N-methylanilide resulted in cleavage of the SÄO bond in the p-toluenesulfonate moiety with formation of N-methyl-N-phenyl-p-toluenesulfonamide and 4,5-bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane disodium salt. Diethyl (4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylate reacted with methylamine to give the corresponding dicarboxamide which was reduced with lithium aluminum hydride to (4S,5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane having chiral carbon and nitrogen atoms.     

2-芳基-(4S,5S)-4,5-双(胺甲酰基)-1,3-二氧戊环的合成

以D-酒石酸二乙酯和芳香醛为原料,经缩醛化、氨解两步反应合成了15个未见文献报道的适合工业化生产庚铂类似物的关键中间体——2-芳基-(4S,5S)-4,5-双(胺甲酰基)-1,3-二氧戊环,产率49%～70%,其结构经1HNMR和MS表征。     

2,2-Dimethyl-5-(5-r-2-furfurylidene)-1,3-dioxane-4,6-diones

2,2-Dimethyl-5-(5-methyl-2-furfurylidene)-1,3-dioxane-4,6-dione crystals were subjected to an x-ray diffraction study. The unit cell of the crystal contains two symmetrically independent A and B molecules that exist in the x-cis conformation, which is stabilized by conjugation between the heteroring and, possibly, an intramolecular hydrogen bond.See [1] for Communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1453–1456, November, 1988.     

Enantioselective Hydrogenation over Chiral Cobalt Complexes with (+)-(1S,2S,5R)-Neomenthyldiphenylphosphine and (-)-(R,R)-2,2-Dimethyl-4,5-bis(diphenylphosphinomethyl)-1,3-dioxolane

The optical yield in enantioselective hydrogenation of methyl -acetamidocinnamate over mono- and diphosphine cobalt(II) complexes CoX₂L₂ [where X = Cl or CF₃SO₃, L = (+)-(1S,2S,5R)-neomenthyl-diphenylphosphine or L2' = (-)-(R,R)-2,2-dimethyl-4,5-bis(diphenylphosphinomethyl)-1,3-dioxolane], which are generated in situ, in the presence of sodium tetrahydridoborate increases with rise in the phosphine-to-metal ratio and hydrogen pressure. The maximal optical yields of (+)-(S)-N-acetylphenylalanine methyl ester attain 40% (CoX₂L₂) and 42% (CoX₂L₂').     

On the Synthesis and Enantiomeric Purity of (S)-4-Acetyl-2,2-Dimethyl-1,3-Dioxolane

The title ketone has been synthesised in 96% e.e. from the corresponding methyl ester and MeLi. The [α]_D value for the product was considerably higher than values previously reported for the enantiomer.     

An improved synthesis of (4S,5S)-2,2-dimethyl-4-phenyl-1,3-dioxan-5-amine

The title compound is prepared in 78% yield using an improved one-pot procedure which does not require final purification.     

Study of Nitrogen- and Sulfur-Containing Heterocycles. 57. Synthesis and Conversion of 4′-Substituted 5-(5-Amino-6-Pyrimidylthio)-2,2-Dimethyl-4,6-Dioxo-1,3-Dioxanes

By reaction of 4-substituted 5-amino-6-mercaptopyrimidines with 5-bromo-2,2-dimethyl-4,6-dioxo-1,3-dioxane, we have obtained 4′-substituted 5-(5-amino-6-pyrimidylthio)-2,2-dimethyl-4,6-dioxo-1,3-dioxanes. We have studied diazotization of these compounds by isoamyl nitrite. In the case of 4′-methoxy- and 4′-dimethylamino-substituted derivatives, we have obtained derivatives of novel heterocyclic systems: pyrimido[5,4-e][1,3,4]thiadiazine and pyrimido[5,4-e][1,3,4]thiadiazine-7-spiro-5′-1,3-dioxane, and in the case of the 4′-isopropylamino-substituted derivative we obtained 4-isopropyl-7-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)-1,2,3-triazolo[5,4-d]pyrimidin-7-ylidene.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 613–623, April, 2005.     

The Synthesis and Biological Activities of [5-(4-Substituted Phenylsulfinyl/Sulfonyl)-1,3-Dimethyl-1H-Pyrazol-4-Yl]-Arylmethanones

Abstract

A novel series of pyrazole derivatives containing substituted phenylsulfinyl/sulfonyl group have been synthesized via the oxidation of intermediate pyrazole sulfoether with H₂O₂ in acetic acid. The novel compounds were characterized by melting point, ¹H NMR, FT-IR, MS, and elemental analysis or HRMS. The biological activity results showed that most of the title compounds exhibit significant fungicidal activities against Alternaria solani Sorauer, Phytophthora capsici, and Corynespora cassiicola.

[Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.]     

2,2-Dimethyl-5-(5-R-2-furfurylidene)-1,3-dioxane-4,6-diones. 4. Synthesis,stereostructures, and properties of thiophene analogs

The reaction of 2-formylthiophenes with Meldrum's acid gave the corresponding thenylidenedioxanediones, which, in contrast to the furfurylidene derivatives, have an s-trans conformation of the mutual orientation of the thiophene ring and the exocyclic double bond. Thenyldioxanediones were synthesized by the selective hydrogenation of the exocyclic double bond.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1338–1342, October, 1989.