Synthesis and aminolysis of N-(bicyclo[2.2.1]hept-5-en-endo-2-ylmethyl)-N-(oxiran-2-ylmethyl)(7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonamide

A new N-(oxiran-2-ylmethyl) (glycidyl) derivative has been obtained by reaction of N-(bicyclo-[2.2.1]hept-5-en-endo-2-ylmethyl)(7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonamide with epichlorohydrin. Its epoxidation and aminolysis have been studied, and the regioselectivity of these transformations has been determined by IR and ¹H NMR spectroscopy and mass spectrometry.     

Synthesis of halomethyl-substituted bicyclo[2.2.1]hept-2-yl(meth)acrylates

Russian Journal of Applied Chemistry - Bicyclic esters, which are reactive monomers for the synthesis of new polymeric products and also of organic compounds, were synthesized by the reaction of...     

Experimental and theoretical study of the reaction between bicyclo[2.2.1]hept-5-en-endo-2-ylmethylamine and 2-[(2-allylphenoxy)methyl]oxirane

In reactions of bicyclo[2.2.1]hept-5-en-endo-2-ylmethylamine with 2-[(2-allylphenoxy)methyl]oxirane alongside the product of amine monoalkylation a compound was obtained and isolated by chromatography on silica gel resulting from the reaction of the monoalkylated substance with the initial epoxide. The structure of new aminoalcohols and the regiochemistry of the oxirane opening were examined using IR, 1H NMR, and mass spectra. The features of the reaction mechanism were considered applying quantum-chemical calculations in the level of theory PCM/B3LYP/6-3aG(d).     

Synthesis of bicyclo[2.2.1]hept-5-enyl methyl esters of haloacetic acids

Synthesis of norbornenyl methyl esters of a number of haloacetic acids via [4+2] cycloaddition of cyclopentadiene to allyl esters of these acids was examined. The yield and isomer composition of the synthesized compounds were examined in relation to the reaction conditions, and the best conditions for their preparation were found.     

Synthesis and Epoxidation of 5-(2-Aminoethyl)bicyclo[2.2.1]hept-2-ene Derivatives

A number of derivatives of 5-(2-aminoethyl)bicyclo[2.2.1]hept-2-ene (85-90% of the endo isomer) were synthesized by reactions with p-nitrobenzenesulfonyl chloride, p-toluenesulfonyl chloride, benzoyl chloride, p-nitrobenzoyl chloride, benzyl isocyanate, m-tolyl isocyanate, phenyl isothiocyanate, and endic anhydride. By reactions of the resulting sulfon- and carboxamides with peroxyphthalic acid generated in situ from phthalic anhydride and 40-45% hydrogen peroxide the corresponding epoxy derivatives were obtained. These reactions were not accompanied by heterocyclization into azabrendane derivatives, which is typical of homologous N-(p-nitrophenylsulfonyl)-endo-5-aminomethylbicyclo[2.2.1]hept-2-ene.     

Some chemical transformations of 5-(propyn-2-yl)bicyclo[2.2.1]-2-heptene

Conclusions The Grignard reagent, obtained from 5-(propyn-2-yl)bicyclo[2.2.1]-2-heptene, reacts easily with Ac₂O, Et₂SiCl₂, Me₃SiCl, and acrolein to give in high yields [2.2.1]bicyclo-2-heptene derivativesthat contain in the side chain either an acetyl, diethylsilyl, trimethylsilyl, or a hydroxypropen-1-yl group. The Mannich reaction was also run with 5-(propyn-2-yl)bicyclo[2.2.1]-2-heptene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2586–2589, November, 1982.     

Experimental and theoretical study on the reaction of bicyclo[2.2.1]hept-5-en-endo-2-ylmethanamine with glycidyl ethers

Reactions of bicyclo[2.2.1]hept-5-en-endo-2-ylmethanamine with phenyl, 4-methylphenyl, 3-methylphenyl, 2-methylphenyl, 4-methoxyphenyl, cyclohexyl, and cyclohexenyl 2,3-epoxypropyl ethers gave the corresponding N-mono- and N,N-bis(3-R-oxy-2-hydroxypropyl) derivatives. The structure of the newly synthesized amino alcohols and regioselectivity of oxirane ring opening were determined by IR spectroscopy, ¹H and ¹³C NMR, and mass spectrometry. The reaction mechanism was studied by quantum chemistry at the PCM/B3LYP/6-31G(d) level of theory.     

One-pot palladium-catalyzed synthesis of 2,3-disubstituted bicyclo[2.2.1]heptanes and bicyclo[2.2.1]hept-5-enes

A new and highly stereoselective palladium-catalyzed synthesis is reported, based on two subsequent insertions of the bicyclo[2.2.1]heptene system into an aryl or vinylpalladium bond, formed in situ from aryl or vinyl bromides.     

2-Chlorobicyclo[2.2.1]hept-5-ene-2-carboxamide and 2-chlorobicyclo[2.2.1]heptane-2-carboxamide as precursors of bicyclo[2.2.1]hept-5-en-2-one and bicyclo[2.2.1]heptan-2-one: resolution,absolute configuration and hydrogen-bonding properties

The absolute configuration of bicyclo[2.2.1]heptan-2-one has not been correlated with a crystal structure of a chemical precursor. The only chemical correlation available had an ambiguity, which could have reversed the assignment. Herein, we report the resolution of 2-chlorobicyclo[2.2.1]hept-5-en-2-exo-carboxamide on a cellulose triacetate column and the crystal structures of the enantiomerically pure and racemic α-chloroamide. We found the absolute configuration (1R,2R,4R) for the (+)-enantiomer of the α-chloroamide. This compound was converted to (+)-bicyclo[2.2.1]hept-5-ene-2-one by base hydrolysis, and the 5,6-unsaturated compounds converted to the saturated congeners. This is the first unambiguous experimental determination of the absolute configuration of bicyclo[2.2.1]heptan-2-one and of bicyclo[2.2.1]hept-5-ene-2-one. The three crystal structures of 2-chlorobicyclo[2.2.1]hept-5-en-2-exo-carboxamide reported herein reveal H-bonded dimers, with two distinct orientations of the bicyclic portion relative to the carboxamide dimer. In the racemic crystal, each dimer is composed of two enantiomers, and the bicyclic portions have their bridge carbon atom (C-7) on opposite sides of the H-bonded carboxamide dimer moiety. In the enantiomerically pure crystals, the major dimer had both C-7 atoms on the same side of the carboxamide dimer moiety while the minor dimer had the C-7 atoms on opposite sides. The dimers are present in solution, and can be easily monitored.     

Interconversion of bicyclo[2.2.1]hept-2-yne and 5-bicyclo[2.1.1]hexylidenecarbene

This work provides unambiguous results for the full equilibration of cycloalkyne 2 with its isomeric ring-contracted vinylidene 3 prior to their reaction with 2,3-dihydropyran (4), as evidenced by the products formed when 2 and 3 are produced directly from their precursors having bicyclo[2.2.1]heptyl and bicyclo[2.1.1]hexyl skeletons, respectively.     

Novel thermolytic transformations of n-benzoyl 2-aza 3-oxa bicyclo(2.2.1)hept-5-ene and n-benzoyl 2-aza 3-oxa bicyclo(2.2.1)heptane

Novel thermolytic pathways were encountered in careful studies with N-benzoyl 2-aza 3-oxa bicyclo (2.2.1)heptene (1) and N-benzoyl 2-aza 3-oxa bicyclo(2.2.1)heptane (2). Compound 1 thermally fragments by four major pathways, namely, (3,3)-sigmatropic shift, (4 + 2) cycloreversion, N-O rupture and C-N homolysis. The (3,3)-sigmatropic shift provides a novel route to unusual, bicyclic heterocycles. Electron withdrawing aryl groupings tend to promote the (3,3)-sigmatropic shift pathway over others. The (4 + 2)-cycloreversion of 1 leads to nitroso carbonyl benzene and cyclopentadiene. The weak σ bonds of PhCONO undergo ready homolysis. The intermediate arising from N-O rupture leads to a cyclopentenone radical similar to that involved in the PG endoperoxide → PGE change. This radical either combines with benzoyl radical leading to 4-dibenzoylamino cyclopentenone or is transformed to an enamide by loss of hydrogen, which, in turn, undergoes (4 + 2)-cycloaddition with cyclopentadiene leading to a novel spiro adduct. The C-N rupture leads to the formation of benzanilide.Nitrosocarbonyl benzene is a powerful electrophile. With cyclohexene it forms a hydroximic ester, initiated by nucleophile acceptance at the CO oxygen. In contrast, it reacts with P(OMe)₃ leading to diphenylurea via nucleophile acceptance at NO oxygen. Thermolysis of 2 proceeds largely by N-O rupture, similar to that normally observed in the PG endoperoxide → PGE change.     

Synthesis and corrosion-protective properties of acetylenic esters of bicyclo[2.2.1]hept-5-ene-2-carboxylic acid

A procedure was developed for preparing acetylenic esters of bicyclo[2.2.1]hept-5-ene-2-carboxylic acid. The structures of the compounds were confirmed by IR and ¹H NMR spectroscopy. The Kovats indices of the compounds were determined, and their boiling points were estimated by gas-liquid chromatography. The protective properties of the esters against acid corrosion of steel were studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 8, 2004, pp. 1331–1335.Original Russian Text Copyright © 2004 by Mamedov.     

Basicity of {(2-amino)- and (2-aminomethyl)bicyclo[2.2.1]hept-3-yl}anilines in nitromethane

Ionization constants of {(2-amino)-bicyclo[2.2.1]-hept-3-yl}anilines and {(2-aminomethyl)bicyclo [2.2.1]-hept-3-yl}anilines in nitromethane have been determined by potentiometric titration. Due to high values of pK _{a 1} ^BH+ and pK _{a 2} ^BH+ (close to known adamantane-containing diamines) the studied compounds are promising candidates for preparation of (co)polyimides with a complex of excellent utilitarian properties.     

Microwave spectra and dipole moments of bicyclo [2.2.1]-hepta-7-one and bicyclo [2.2.1]hept-2-en-7-one

The microwave spectra of bicycle [2.2.1] hepta-7-one (I), bicyelo [2.2.1] hept-2-en-7-one (II), and exo-5,6-bisdeuteriobicyclo [2.2.1] hept-2-en-7-one (III) have been recorded in the region between 26.5 and 40.0 GHz. The rotational constants in the order A, B, C for the title compounds are 2773.24±0.31, 2301.74±0.04, and 2133.96±0.02 (I); 2979.22±0.08, 2418.60±0.01, and 2235.51±0.01 (II); and 2789.67±0.06, 2385.24±0.01, and 2150.60±0.01 (III). The rotational constants of four vibrationally excited states were also determined for (II). Quadratic Stark effect measurements on the 7₁₆ ← 6₁₅ transition of (I) gave ¦μ_a¦=2.99±0.03. Similar measurements on two 5 ← 4 and 4 ← 3 transitions of (II) gave ¦μ_a¦=2.88±0.03, ¦μ_b¦=0.39±0.03, ¦μ_c¦=0, and ¦μ_total¦=2.91±0.04.     

Soluble polyimides and copolyimides with increased hydrolytic stability that are based on [(2-amino)- and (2-aminomethyl)bicyclo[2.2.1]hept-3-yl]anilines

On the basis of [(2-amino)- and (2-aminomethyl)bicyclo[2.2.2]hept-3-yl]anilines, new soluble polyimides and copolyimides are synthesized. They are characterized by high thermal stability and increased hydrolytic stability that significantly surpass those of aromatic polyimides.     

Synthesis of <Emphasis Type="Italic">para</Emphasis>-substituted bicyclo[2.2.1]hept-5-en-2-ylmethyl benzoates

para-Substituted bicyclo[2.2.1]hept-5-en-2-ylmethyl benzoates were synthesized by the Diels-Alder reaction of cyclopentadiene with the corresponding para-substituted allyl benzoates, and optimal reaction conditions were found. The product structure was confirmed by independent synthesis and IR and ¹H NMR spectroscopy.     

Synthesis of monoethers by addition of aliphatic diols to bicyclo[2.2.1]hept-2-enes

Addition of aliphatic diols to bicyclo[2.2.1]hept-2-ene and its 5-alkyl-substituted derivatives in the presence of naphthalene-1,5-disulfonic acid leads to the formation of the corresponding bicyclo[2.2.1]hept-2-yl monoethers in high yields.