Reactions of diazoalkanes with unsaturated compounds 16. Catalytic reactions of diazomethane with 2-alkenyl-1,3-oxazolidines and 2-alkenyl-1,3-oxathiolanes

The influence of 1,3-oxazolidine and 1,3-oxathiolane fragments in substituted alkenes on the direction of their catalytic reaction with diazomethane has been investigated. The olefins bearing an oxazolidine substituent in the α- or γ-position and an oxathiolane substituent in the γ-position relative to the C=C bond react with diazomethane in the presence of Pd(acac)₂ selectively resulting in cyclopropanation products. The use of Cu(OTf)₂ does not result in cyclopropanation; however Cu(OTf)₂ catalyzes the reaction of diazomethane with 2-(alk-1-enyl)-1,3-oxathiolanes yielding 2,3,5,6-tetrahydro-1,4-oxathiocines formed through the [2,3]-sigmatropic rearrangement of the intermediate sulfonium ylides. For Part 15 see Ref. 1. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 604–608, March, 2008.     

Novel azetidinones for carbapenems and fragmentation in the allylamine precursor analogue

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Cu(OAc)2-2,4-lutidine-ZnCl2 as an effective catalyst of functionalization of isobutylene oligomers and 1,2-polybutadiene with methyl diazoacetate

The possibility of [1+2]-cycloaddition of methoxycarbonylcarbene generated by catalytic decomposition of methyl diazoacetate in the presence of the Cu(OAc)₂-2,4-lutidine-ZnCl₂ system to the carbon-carbon double bound in isobutylene oligomers and syndiotactic 1,2-polybutadiene was examined. A comparative analysis of physicochemical properties of the starting compounds and their functionalized products was performed.     

Phosphazenes: I. Reactions with electron-deficient alkenes

Triphenylphosphazenes reacted with methyl vinyl ketone, methyl acrylate, methyl methacrylate, and dimethyl maleate to give the corresponding substituted dihydropyrazoles.     

The Claisen rearrangement in the aminophenol series

Novel compounds, dihydropyranylaminophenols, were synthesized by condensation of 3,4-dibromo-4-methyltetrahydropyran with aminophenols followed by the Claisen rearrangement ofO-andN-substituted products. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 517–520, March, 1999.     

Structure Determination of Diastereoisomeric Thia-Michael Bis-adducts of Methyl (5-Methylidene-4-oxocyclopent-2-en-1-yl)acetate with Ethanethiol

Russian Journal of Organic Chemistry - Three of the four possible diastereoisomeric thia-Michael addition products of the reaction of methyl (5-methylidene-4-oxo-cyclopent-2-en-1-yl)acetate with...     

Bis(Allyloxycarbonyl)methano derivatives of fullerene C<Subscript>60</Subscript>

Mono-, bis-, tris-, tetrakis-, and hexakis-substituted cyclopropanation products of fullerene C₆₀ with diallyl malonate were synthesized according to Bingel-Hirsch. Except for the monocyclopropanation product, all other adducts were isolated as mixtures of regioisomers.     

New catalytic system Cu(OAc)<Subscript>2</Subscript>—2,4-lutidine—ZnCl<Subscript>2</Subscript> for olefin cyclopropanation with methyl diazoacetate

A new efficient catalytic system consisting of Cu(OAc)₂, 2,4-lutidine, and ZnCl₂ was found for the cyclopropanation of unsaturated compounds with methyl diazoacetate. In the case of conjugated dienes, the process occurs regioselectively at the most alkylated C=C bond. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1750–1752, August, 2008.