4904-61-4Relevant academic research and scientific papers
PROCESS FOR PREPARING CYCLODODECATRIENE
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Page/Page column 3, (2008/06/13)
Preparation of cyclododecatriene in a continuous or discontinuous process by trimerization of butadiene in the presence of a catalyst system and a solvent, the crude cyclododecatriene obtained being able to be isolated by means of distillation. The cyclooctadiene formed as by-product can likewise be isolated from the crude product.
Copolymerization of styrene with unsaturated compounds contained in the bottoms of distillation of the recycling solvent
Nikulin,Filimonova
, p. 157 - 161 (2007/10/03)
Radical-induced copolymerization of styrene with unsaturated compounds contained in the toluene distillation bottoms from production of butadiene rubber was studied. The dependences of the yield of the polymeric products on the nature of the hydroperoxide
Titanium-catalyzed [4+2] and [6+2] cycloadditions of 1,4-bis(trimethylsilyl)buta-1,3-diyne
Kaagman, Jan-Willem F.,Rep, Marco,Horacek, Michal,Sedmera, Petr,Cejka, Jiri,Varga, Vojtech,Mach, Karel
, p. 1722 - 1728 (2007/10/03)
The (C2H5)2AlCl/TiCl4 catalyst induces the [4+2] cycloaddition of butadiene or the [6+2] cycloaddition of 1,3,5-cycloheptatriene (CHT) to individual acetylenic moieties of 1,4-bis(trimethylsilyl)buta-1,3-diyne (BSD). Heating of the 2:1 butadiene adduct, bis(2-trimethylsilylcyclohexa-1,4-dien-1-yl), to 250°C yields 2,2′-bis(trimethylsilyl)biphenyl. The 1:1 adduct of BSD with CHT, 7-trimethylsilyl-8-trimethylsilylethynylbicyclo[4.2.1]nona-2,4-diene, is obtained as virtually the only product if the initial molar ratio CHT:BD equal to 1.86 is used.
THERMAL CONVERSION OF 1,5,9-TRIYNES. CYCLOADDITIONS OR SIGMATROPIC SHIFTS?
Dower, William V.,Vollhardt, K. Peter C.
, p. 1873 - 1882 (2007/10/02)
The gas phase pyrolyses of variously labeled 1,5,9-decatriynes (1) and 1,5,9-cyclododecatriynes (2) were investigated to determine possible modes of thermal isomerizations.Conditions included temperatures in the range 400-600 deg C, pressures of 40 -10E-4 Torr, and contact times of ca 1 ms to 15 s.The labeling patterns in 1 and 2 were chosen such as to be able to distinguish direct intramolecular cycloadditions of the alkyne units to form an aromatic ring (perhaps with subsequent rearrangements), and sigmatropic shifts of the 1,5-diyne moieties.Methods for synthesizing the isotopically (particularly (13)C) labeled triynes were devised and implemented.The route to 5,6-(13)C2-1,5,9-decatriyne (1c) made use of a new procedure for the synthesis of symmetrically disubstituted alkynes involving coupling between two equivalents of an alkyl copper reagent and diiodoacetylene-(13)C2.The synthesis of 1,10-(13)C2-1,5,9-cyclododecatriyne (2b) was accomplished starting with K(13)CN, elaboration to labeled diethyl succinate, a crucial bis-Wittig condensation to labeled 1,5,9-cyclododecatriene 10, and bromination-dehydrobromination of the latter (NaOH-ethylene glycol).Products from the pyrolysis of unlabeled 1a included dicyclobutabenzene, naphtalene and 3,4-dimethylidene-1-(but-3-ynyl)cyclobutene.Pyrolysis of 1b gave 3,6-dideuteriodicyclobutabenzene and partially deuterated naphthalene, that of 1c produced 1,2-(13)C2-dicyclobutabenzene and 9,10-(13)C2-naphthalene.While the pyrolysis of 2a resulted in hexamethylidenecyclohexane (hexaradialene), 2b furnished 1,4-(13)C2-hexaradialene.The results rule out the occurence of cycloadditions of the alkyne units, but are consistent with the intervention of a series sigmatropic shifts which connect starting materials with products.
CATALYTIC REACTIONS INVOLVING BUTADIENE. III. OLIGOMERIZATION WITH CATIONIC BIS(TRIPHENYLPHOSPHINE)(η3-ALLYL) COMPLEXES
Grenouillet, P.,Neibecker, D.,Tkatchenko, I.
, p. 213 - 222 (2007/10/02)
The bis(triphenylphosphine)(η3-crotyl)nickel cation is a catalyst precursor for the oligomerisation of butadiene to cyclic or linear dimers.Polymers and oligomers are also produced in variable amounts.The product distributions depend strongly on the type of solvent used and on the nature of co-catalysts.In the aprotic polar solvent DMF, the starting complex undergoes disproportionation, leading finally to a zerovalent nickel-phosphine catalyst.In protic solvents (alcohols) a cationic hydridonickel-phosphine catalyst is produced, but addition of sodium methoxide induces the formation of the zerovalent nickel-phospnine, therefore accounting for the changes in product selectivities.
KINETICS AND MECHANISM OF THE COTRIMERIZATION OF BUTADIENE WITH STYRENE IN THE PRESENCE OF THE CATALYTIC SYSTEM (C5H7O2)2Ni + (C2H5)3Al + (C6H5)3P
Akhmedov, V. M.,Khanmetov, A. A.,Azizov, A. G.
, p. 1479 - 1485 (2007/10/02)
The kinetic relationships governing the cotrimerization of 1,3-butadiene with styrene into 1-phenyl-1,4,8(9)-decatriene in the presence of the catalytic system consisting of nickel acetylacetonate, triethylaluminum, and triphenylphosphine were investigated.The principal kinetic parameters of the cotrimerization reaction were determined.
