Propyl acetylene

Another complex involving the formation of a cyclopentadienyl unit is obtained from the interaction of ethyl or propyl acetylene with Fe3(CO)i2 117). The products contain the complexes Fe3(CO)7(HC2R)4 (R = Et, re-Pr), and the crystal structure of the ethyl derivative indicates the presence of the substituted 1,2,3-triethylcyclopentadienyl group bonded to one iron center with an ethylallyl group cr- and n-bonded to the three metal centers. The formation of adducts of this type must involve the fission of the C=C bond of the acetylene. 

Pyrolysis of tris(heptafluoroisopropyl)-1,2,4-triazine (329) affords bis(heptafluoroiso-propyl)acetylene and perfluorobutyronitrile, besides nitrogen (79JCS(P1)1978, 80JCS(P1)2254). The thermal fragmentation of this compound is analogous to the mass spectral fragmentation of many other 1,2,4-triazines. 

The discovery of junipal focused the attention of Sorensen, who had been investigating the occurrence of polyacetylenes in Com-positae, on the possibility that these acetylenes were accompanied by thiophenes. From Coreopsis grandiflora Hogg ex sweet, 2-phenyl 5-(1-propynyl) thiophene (240) was isolated and its structure confirmed by synthesis of the tetrahydro compound, 2-phenyl-5-n-propyl-thiophene. From the root of tansy, the cis and trans isomers of methyl 5-(l-propynyl)-2-thienylacrylate (241) have been isolated. The total synthesis of trans (241) was achieved by reacting junipal with methylcarbethoxy triphenylphosphonium bromide (Wittig reaction) Several monosubstituted thiophenes, (242), (243), and... 

C ( propyl) N phenylmtrone to N phenylmaleimide, 46, 96 semicarbazide hydrochloride to ami noacetone hydiochlonde, 46,1 tetraphenylcyclopentadienone to diphenyl acetylene, 46, 44 Alcohols, synthesis of equatorial, 47, 19 Aldehydes, aromatic, synthesis of, 47, 1 /3-chloro a,0 unsaturated, from ke tones and dimethylformamide-phosphorus oxy chloride, 46, 20 from alky 1 halides, 47, 97 from oxidation of alcohols with dimethyl sulfoxide, dicyclohexyl carbodumide, and pyndimum tnfluoroacetate, 47, 27 Alkylation, of 2 carbomethoxycyclo pentanone with benzyl chloride 45,7... 

Mit Bis-[2-methyl-propyl]-aluminiumhydrid gelingt die Monohydroaluminierung mit-telstandiger Acetylene bei 40-80° stereoselektiv unter d5-Addition13 zu cis-Alken-(l)-... 

ETHYLENE GLYCOL ETHYL MERCAPTAN DIMETHYL SULPHIDE ETHYL AMINE DIMETHYL AMIDE MONOETHANOLAMINE ETHYLENEDIAMINE ACRYLONITRILE PROPADIENE METHYL ACETYLENE ACROLEIN ACRYLIC ACID VINYL FORMATE ALLYL CHLORIDE 1 2 3-TRICHLOROPROPANE PROPIONITRILE CYCLOPROPANE PROPYLENE 1 2-DICHLOROPROPANE ACETONE ALLYL ALCOHOL PROPIONALDEHYDE PROPYLENE OXIDE VINYL METHYL ETHER PROPIONIC ACID ETHYL FORMATE METHYL ACETATE PROPYL CHLORIDE ISOPROPYL CHLORIDE PROPANE... 

METHYL ETHYL SULPHIDE N-PROPYL AMINE ISOPROPYL AMINE TRIMETHYL AMINE MALEIC ANHYDRIDE VINYL ACETYLENE... 

From the electronic populations on the vinylic hydrogens, the acidity of vinylic C—H was estimated to be higher in cyclopropenone than in cyclopropene (0.684 e/ 0.776 e). This agrees with kinetic measurements of the H-D-exchange at n-propyl cyclopropenone23 which showed an acidity of the vinylic C—H even higher than that of the acetylenic C—H in the reference compound propargyl alcohol. 

In the area of reaction energetics. Baker, Muir, and Andzehn have compared six levels of theory for the enthalpies of forward activation and reaction for 12 organic reactions the unimolecular rearrangements vinyl alcohol -> acetaldehyde, cyclobutene -> s-trans butadiene, s-cis butadiene s-trans butadiene, and cyclopropyl radical allyl radical the unimolecular decompositions tetrazine -> 2HCN -F N2 and trifluoromethanol -> carbonyl difluoride -F HF the bimolecular condensation reactions butadiene -F ethylene -> cyclohexene (the Diels-Alder reaction), methyl radical -F ethylene -> propyl radical, and methyl radical -F formaldehyde -> ethoxyl radical and the bimolecular exchange reactions FO -F H2 FOH -F H, HO -F H2 H2O -F H, and H -F acetylene H2 -F HC2. Their results are summarized in Table 8.3 (Reaction Set 1). One feature noted by these authors is... 

Type 4A sieves. The pore size is about 4 Angstroms, so that, besides water, the ethane molecules (but not butane) can be adsorbed. Other molecules removed from mixtures include carbon dioxide, hydrogen sulphide, sulphur dioxide, ammonia, methanol, ethanol, ethylene, acetylene, propylene, n-propyl alcohol, ethylene oxide and (below -30°) nitrogen, oxygen and methane. The material is supplied as beads, pellets or powder. 

Two Russian papers359,360 have described the synthesis and addition of acetylenic esters to dihydro-s-triazines. The triphenyl derivative 281 on heating with DEAD in ether for 3 hours gave 80% of286, presumably via 285. The diphenyl propyl derivative (282) added Michael fashion to... 

Abbreviations arene, i/6-benzene or substituted benzene derivative bipy, 2,2 -bipyridyl Bu, Bu", Bu, iso-, n-, or rerf-butyl COD, 1,5-cyclo-octadiene Cp, /5-C5H5 DAD, dimethyl-acetylene dicarboxylate dam, 1,2-bis(diphenylarsino)methane DBA, dibenzylideneacetone DMF, A. A -dimethylformamide dpe, l,2-bis(diphenylphosphino)ethane dpen, os-l,2-bis(di-phenylphosphino)ethylene dpm, 1,2-bis(diphenylphosphino)methane ESR, electron spin resonance F6-acac, hexafluoroacetylacetone FN, fumaronitrile MA, maleic anhydride Me, methyl MLCT, metal ligand charge transfer phen, 1,10-phenanthroline Pr , Pr", iso- or n-propyl py, pyridine RT, room temperature TCNE, tetracyanoethylene tetraphos, (Ph2PCH2CH2)jP THF, tctrahydrofuran Xylyl, 2,6-Me2C6H3. 

See 2-(4-Chlorophenyl)-2-propyl l-(l,l-dimethyl-2-pentyn-4-enyl) peroxide (below) See other ACETYLENIC PEROXIDES, DIALKYL PEROXIDES... 

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