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Penta cyclohexyl

Abbreviations aapy, 2-acetamidopyridine Aik, alkyl AN, acetoniuile Ar, aryl Bu, butyl cod, 1,5-cyclooctadiene COE, cyclooctene COT, cyclooctatetraene Cp, cyclopentadienyl Cp , penta-methylcyclopentadienyl Cy, cyclohexyl DME, 1,2-dimethoxyethane DME, dimethylformamide DMSO, dimethyl sulfoxide dmpe, dimethylphosphinoethane dppe, diphenylphosphinoethane dppm, diphenylphosphinomethane dppp, diphenylphosphinopropane Et, ethyl Ec, feirocenyl ind, inda-zolyl Me, methyl Mes, mesitylene nb, norbomene orbicyclo[2.2.1]heptene nbd, 2,5-norbomadiene OTf, uiflate Ph, phenyl PPN, bis(triphenylphosphoranylidene)ammonium Pi , propyl py, pyridine pz, pyrazolate pz, substituted pyi azolate pz , 3,5-dimethylpyrazolate quin, quinolin-8-olate solv, solvent tfb, teti afluorobenzobaiTelene THE, tetrahydrofuran THT, tetrahydrothiophene tmeda, teti amethylethylenediamine Tol, tolyl Tp, HB(C3H3N2)3 Tp , HB(3,5-Me2C3HN2)3 Tp, substituted hydrotiis(pyrazol-l-yl)borate Ts, tosyl tz, 1,2,4-triazolate Vin, vinyl. [Pg.167]

On the other hand, in penta- and hexa(spirotetrahydrofuranyl)cyclohexyl systems the chair conformation of the central cyclohexane ring is still preserved (96JA4504). The boat conformation of the cyclohexane ring can be stabilized also by careful substitution. A series of hopanoid hydrocarbons, the D cyclohexane ring prefers the boat conformation by 1.3-2.5 kcal/mol (95JA6532). [Pg.47]

Ac = Acetyl acac = Acetylacetonate bda = Benzylidene-acetone BINOL = l,l -bi-2-naphthol Bn = Benzyl brsm = Yield based on recovered starting material Bu = Bntyl CAN = Ceric anunonium nitrate CBS = Corey/Bakshi/Shibata catalyst [(+) or (—)-(S)-2-methyl-oxazaborolidine] COD = Cyclo-l,5-octadiene COT = Cyclooctatetraene Cp = Cyclopentadienyl Cp = Penta-methylcyclopentadienyl Cy = Cyclohexyl DCC = Dicy-clohexylcarbodiimde DMF = Ai,A-dimethylformainide DMPU = l,3-dunethyl-3,4,5,6-tetrahydro-2(lH)-pyrimidin-one DMSO = Dimethylsnlfoxide dppe = Diphenylphosp-hinoethane dr = Diastereomer ratio dppm = Diphenylphos-phinomethane E = Electrophile ee = Enantiomeric excess EHMO = Extended htickel molecular orbital Et =... [Pg.2014]

Even the propargylic alcohol derivative 35 with an electronically almost unactivated triple bond smoothly undergoes palladium(0)-catalyzed cycloisomerization to give an 85% yield of the allylic alcohol, (3/ , 3a5 )-3-cyclohexyl-4-methylene-3,3a,4,5-tetrahydro-lff-cyclo-penta[c]furan-6-methanol (36)." The substrate molecule containing a rer/-butyldimethylsilyl substituent at the alkyne instead of a hydroxymethyl group, however, again failed to undergo the cycloisomerization, presumably due to steric hindrance. ... [Pg.2285]

Masamune and coworkers have examined the facial selectivity of the (Z)-lithium enolates of 3-penta-none and ethyl cyclohexyl ketone with a series of P-alkoxy aldehydes having stereocenters at both the a-and p-position (equation 110 Table 18). In the six-mernbered chelate, the methyl and R groups are on the same side of the ring, and it may be seen from the data in Table 18 that the nature of R influences the facial preference of the chiral aldehyde. Another example of this effect is seen in equation (54). [Pg.221]

Similar to the reactions of carbocyclic cyclohexyl radicals, axial instead of equatorial substitution in the -position leads to increased axial attack. Thus, in the reaction of the penta-0-acetylmannopyranos-l-y] radical, only axial deuterium trapping products are found, even at 90 °C44. [Pg.637]

Reguiatory FDA 21CFR 172.515 FEMA GRAS Manuf./Distrib. Advanced Synthesis Tech. http //WWW. advancedsynthesis.com, Degussa AG/Health Nutrition http //www.degussa-heaith-nutrition.de, Penta Mfg. http //www.pentamfg. com Cyclohexyl crotonate CAS 31416-78-1... [Pg.1127]

High yields of p-D-ribofuranosides and P-D-glucopyranosides have been obtained by treating l-0-acetyl-2,3,5-tri-0-benzoyl-P-D-ribofuranose and p-o-glu-copyranose penta-acetate, respectively, in dichloromethane with equimolar quantities of an alcohol and tin(iv) chloride at or below room temperature. Several alkyl and cyclohexyl p-D-ribofuranosides were prepared by this method, which was extended to the synthesis of the protected disaccharide 6-0-(2,3,5-tri-0-benzoyl-P-D-ribofuranosyl)-l,2 3,4-di-0-isopropylidene-a-D-galactopyranose. Tin(iv) chloride also catalysed the formation of aryl p-D-ribofuranosides from P-D-ribofuranosyl tetra-acetate. An acetylated precursor has also been used in... [Pg.20]


See other pages where Penta cyclohexyl is mentioned: [Pg.500]    [Pg.500]    [Pg.128]    [Pg.417]    [Pg.297]    [Pg.214]    [Pg.256]    [Pg.239]    [Pg.572]    [Pg.71]   


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