Reaction of arenediazonium tetrafluoroborates with allyl methacrylate in the presence of the thiocyanate anion

Allyl 2-thiocyanato-2-methyl-3-arylpropionates were obtained by the reaction of arenediazonium tetrafluoroborates with allyl methacrylate in a water-acetone (1: 5) medium, involving thiocyanatoarylation by the C=C bond of the methacrylic fragment. Under the examined conditions, the allylic fragment of the biunsaturated compound does not react.     

Crystallization of chiral compounds 3. 3-phenoxypropane-1,2-diol and 3-(2-halophenoxy)propane-1,2-diols

Specific features of melting of crystalline samples of 3-(2-R-phenoxy)propane-1,2-diols with different enantiomeric compositions were studied by differential scanning calorimetry. The melting points and enthalpies of melting for the racemate and individual stereoisomers were determined. Binary phase diagrams were constructed. The entropy of mixing of individual enantiomers in the liquid phase and the free energy of formation of the racemic compound were calculated. The thermochemical data indicate that the racemates are formed upon the crystallization of phenoxy-and 2-fluorophenoxy-containing compounds, while crystallization of the chloro-, bromo-, and iodo-substituted analogs would form racemic conglomerates. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 225—232, February, 2006.     

A novel synthesis of (2S)-3-(2,4,5-trifluorophenyl)propane-1,2-diol by sharpless asymmetric epoxidation method

Synthesis of (2S)-3-(2,4,5-trifluorophenyl)propane-1,2-diol by the Sharpless asymmetric epoxidation reaction has been achieved. 2,4,5-Trifluorobenzaldehyde with methyl 2-(triphenyl-λ⁵-phosphanylidene)acetate gave methyl (E)-3-(2,4,5-trifluorophenyl)acrylate in 83% yield. The reduction of ester group with DibalH followed by Sharpless asymmetric epoxidation gave ((2R,3R)-3-(2,4,5-trifluorophenyl)oxiran-2-yl)methanol. Pd/C-catalyzed hydrogenation of epoxy alcohol furnished (2S)-3-(2,4,5-trifluorophenyl)propane-1,2-diol with >90% ee and 71% yield.     

Effective synthesis of non-racemic prenalterol based on spontaneous resolution of 3-(4-hydroxyphenoxy)propane-1,2-diol

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Reaction of 3-(dimethylamino)-2,2-dimethylpropanal with trialkylphosphites in the presence of acetic anhydride

Russian Journal of General Chemistry -     

Reaction of (chloromethyl)trichlorosilane with 2,2-dimethylpropane-1,3-diol

Russian Chemical Bulletin - (Chloromethyl)trichlorosilane reacts with 2,2-dimethylpropane-1,3-diol to produce α-carbofunctional heterocycles,...     

Reactions of arenediazonium tetrafluoroborates with 3-chloro-2-methylpropene in the presence of potassium chloride,bromide, and thiocyanate

Arenediazonium tetrafluoroborates reacted with 3-chloro-2-methylpropene in the presence of potassium chloride, bromide, and thiocyanate to give the corresponding 1-aryl-3-chloro-2-halo(thiocyanato)-2-methylpropanes. The presence of a copper salt is a necessary condition for the reaction to occur. The yields of the corresponding 1-aryl-3-chloro-2-halo-2-methylpropanes in the Meerwein reaction were approximately twice as low. Introduction of a methyl group to C2 in the 3-chloropropene molecule does not change the reaction regioselectivity.     

Reaction of diazonium salts with transition metals : IX. Reaction of vinyltrimethylsilane with arenediazonium tetrafluoroborates under palladium(0) catalysis

Arenediazonium tetrafluoroborates (ArN₂BF₄ where Ar=Ph, 4-MeC₆H₄, 4-BrC₆H₄, 4-IC₆H₄ and 4-NO₂C₆H₄) reacted easily with CH₂=CHSiMe₃ at 25 δC to give ArCH=CH₂, (E-ArCH=CHSiMe₃ and Ar(Me₃Si)C=CH₂ in excellent yields under palladium(O) catalysis. (E)-ArCH=CHSiMe₃ compounds were obtained predominantly and isolated in good yields by using an excess of CH₂=CHSiMe₃ over ArN₂BF₄. Protodesilylation of the reaction mixture afforded styrene derivatives.     

Reaction of 1,2-bis(cyclopentadienyl)tetramethyl digermane with Ru3(CO)12

We have recently reported a novel rearrangement reaction involving an intramolecular metathesis between M-M and Fe-Fe bonds in the dinuclear iron complexes (Me₂MMMe₂)[η⁵-C₅R₄)Fe(CO)]₂(μ-CO)₂ (M=Si, Ge; R=H, Me):^[1-5].In order to extend the applied range of the rearrangement reaction we tried to synthesize the digermyl briged diruthenium analogues. The results showed a great difference between them.     

用Heck反应合成1-羟基-4-(3-吡啶基)丁-2-酮

在Heck反应条件下,以Ph3P为催化剂配体,由3-卤代吡啶和3-丁烯-1,2-二醇进行偶合可以得到1-羟基-4-(3-吡啶基)丁-2-酮,具有原料易得、合成方法简单的优点.     

Chemistry of Dioxacyclanes: VII. Synthesis of 1,3-Dioxolane Derivatives from 3-(2-Propenyloxy)propane-1,2-diol and Their Properties

2,4-Disubstituted 1,3-dioxolanes were synthesized by reactions of benzaldehyde, its para-chloro derivatives, as well as 3-cyclohexenecarboxaldehyde with 3-(2-propenyloxy)-1,2-propanediol. Theproducts were brought into bromination, dichlorocarbene addition, and epoxidation reactions. It is found that when both components of the heterogeneous reaction of dioxolane ring formation have a double bond, the acid catalyst in strongly deactivated.     

Synthesis and study of organic nitrates of heterofunctional series. 5. Synthesis of 3,3-bis(hydroxymethyl)oxetane mono- and dinitrates and 2,2-bis(hydroxymethyl)propane-1,3-diol (pentaerythritol) mono- and dinitrates

New procedures were developed for the synthesis of 3,3-bis(hydroxymethyl)oxetane dinitrate (1) by O-nitration of the corresponding glycol (3) or its mononitrate (6), which were prepared by the reactions of 2,2-bis(hydroxymethyl)propane-1,3-diol (pentaerythritol) (2) mono- (4) and dinitrates (5), respectively, with alkali. A new method was devised for the synthesis of compounds 4 and 5 by the reaction of tetraol 2 with concentrated HNO₃ in dichloroethane. The structures of compounds 1 and 6 were established by X-ray diffraction analysis.