61771-84-4Relevant academic research and scientific papers
New Pathways to Precursors of Pentalene
You, Shaochun,Chai, Shengyong,Schwarz, Nadine,Neuenschwander, Markus
, p. 1627 - 1638 (2007/10/03)
Pentalene dimers 2 and 3 are easily available in moderate yields by CuCl2-induced oxidative coupling of dilithium-pentalenediide (5) (Scheme 1).On the other hand, NBS bromination of 1,5-dihydropentalene (4) or of 1,2-dihydropentalene (8) gives unstable 1-bromo-1,2-dihydropentalene (9), while subsequent in-situ elimination with Et3N exclusively gives syn-cis-pentalene dimer 2 in moderale yields (Scheme3).NMR-Spectroscopic evidence for compounds 2. 3. and 9 is presented, and mechanistic alternatives for the formation of pentalene dimers 2 and 3 are discussed.
Isomerization of Dihydropentalenes and Reaction with Tetracyanoethylene
Pauli, Alfred,Kolshorn, Heinz,Meier, Herbert
, p. 1611 - 1616 (2007/10/02)
The six isomeric dihydropentalenes 1-6 are connected by various H-shifts (Scheme 1), which are investigated in gas phase pyrolyses.Thermodynamic control leads irreversibly from equilibria between 1-6 to styrene (15) via 1-vinylfulvene (14).The catalytic isomerization 1,5-DHP (4) 1,2-DHP (1) at room temperature is of special preparative interest.Reaction of the dihydropentalenes with tetracyanoethylene yields the adduct 24 of 1, the adducts 25 and 26 of 3 and 5, respectively, and the double adduct 22 of 4. 2 and 6 cannot be trapped with TCNE under flash pyrolysis conditions.
Dihydropentalenes
Meier, Herbert,Pauli, Alfred,Kolshorn, Heinz,Kochhan, Peter
, p. 1607 - 1610 (2007/10/02)
Applying the MNDO method the enthalpies of formation and the frontier orbitals of the six isomeric dihydropentalenes 1-6 have been calculated .An easy preparative access for the energy lower systems 1-4 is provided by the thermolysis of cyclooctatetraene (8) performed under different conditions and by different workup 1-4 were characterized by 1H- and 13C-NMR spectroscopy.
The Pyrolysis of Cubane; an Example of a Thermally Induced Hot Molecule Reaction
Martin, Hans-Dieter,Urbanek, Thomas,Pfoehler, Peter,Walsh, Robin
, p. 964 - 965 (2007/10/02)
The pressure dependence of the product distribution of cubane pyrolysis supports a mechanism involving cyclo-octatetraene formed in a highly vibrationally excited state through the release of ring strain energy.
MECHANISM OF THE THERMAL CONVERSION OF TETRACYCLO(3.3.0.02,4.03.6)OCT-7-ENE INTO DIHYDROPENTALENES
Stapersma, J.,Rood, I. D. C.,Klumpp, G. W.
, p. 2201 - 2212 (2007/10/02)
One of a number of possible mechanisms has been established for the title reaction.
The Thermolysis of Tetracyclo2,4.03,6>oct-7-ene, a New Entry into (CH)8 Systems
Klumpp, Gerhard W.,Stapersma, Johan
, p. 670 - 671 (2007/10/02)
At 270-500 deg C tetracyclo2,4.03,6>oct-7-ene is converted into equilibrating dihydropentalenes within 1-2 s.
