Isomerization of Bicyclo(2.2. 1 )-2,5-heptadiene to Cycloheptatriene

Halper, Warren; Gaertner, G. W.; Swift, Elijah; Pollard, Glenn E.

doi:10.1021/ie50584a029

Cited by 21 publications

(7 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Early experimental work on the C 7 H 8 system includes studies of pyrolysis of NBD and cycloheptatriene (CHT), isomerization of CHT to TOL, − and interconversion between QC and NBD. , More recently, there have been reports of QC photochemistry, quantum calculations of isomerization energetics, and photodetachment and flow tube studiesof C 7 H 7 - produced by deprotonation of QC and its isomers . In this latter study, the gas-phase acidity order of these C 7 H 8 isomers was determined along with the C−H bond dissociation energy of QC.…”

Section: Introductionmentioning

confidence: 96%

“…The thermochemistry for both the neutral and ionic systems is summarized in Figure 1. The heats of formation and barrier heights have been taken from Lias et al, 8 Bach et al, 9 Birely and Chesick, 10 and Lishan et al 11 Early experimental work on the C 7 H 8 system includes studies of pyrolysis of NBD and cycloheptatriene (CHT), isomerization of CHT to TOL, [12][13][14][15] and interconversion between QC and NBD. 16,17 More recently, there have been reports of QC photochemistry, 11 quantum calculations of isomerization energetics, 9 and photodetachment 18 and flow tube studies 19 of C 7 H 7produced by deprotonation of QC and its isomers.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene

Anderson

1998

J. Phys. Chem. A

View full text Add to dashboard Cite

Pyrolysis and isomerization of the C7H8 isomers quadricyclane, norbornadiene, cycloheptatriene, and toluene have been studied in a micro-flow tube reactor with detection/isomer identification by guided-ion beam tandem mass spectrometry. The methodology permits pyrolysis studies with product isomer identification with samples of only a few milligrams. The samples are premixed with buffer gas and then passed through a temperature-controlled flow tube reactor with millisecond residence time. The sample/pyrolysis products exiting the flow tube are ionized by methane chemical ionization (CI), and both CI mass spectra and low-energy collision-induced dissociation were used to determine the composition. For the experimental residence time, toluene and cycloheptatriene are stable over the 298−998 K temperature range. Decomposition of norbornadiene sets in at ∼600 K. The dominant decomposition processes are acetylene elimination via a retro-Diels−Alder reaction and isomerization to toluene. Quadricyclane begins to decompose at ∼500 K, and the dominant decomposition processes are the acetylene elimination and isomerization to toluene, with a small amount of norbornadiene production. The results are discussed in relation to previous studies at lower temperatures/longer times.

show abstract

Section: Introductionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene

Anderson

1998

J. Phys. Chem. A

View full text Add to dashboard Cite

show abstract

“…(1,2) in the hydrolysis of n-propyl halides and sulphonates appeared to provide confirmation of the suggestion that there was a loss of torsional freedom coupled with lesser effects on bending and stretching frequencies as a consequence of the close juxtaposition of the terminal inethyl group, the nucleophilic water, and the leaving group (3). By extension of this argument, the y-deuterium isotope effect seemed to provide a means of exploring the argiiineilts advanced by Dostrovslry, Hughes, and Ingold (4) about enhanced steric hindrance to nucleophilic displaceinent froill isobutyl and neopentyl groups.…”

mentioning

confidence: 61%

THE THERMAL UNIMOLECULAR DECOMPOSITION OF Δ^2,5-BICYCLO[2.2.1]HEPTADIENE

Roquitte¹

1964

Can. J. Chem.

View full text Add to dashboard Cite

The vapor phase thermal decomposition of A2-5-bicyclo[2. 2.1]heptadiene, BCEID[2. 2.11, has received some attention previously (1, 2); recently the kinetic paraineters of the thermal decomposition of BCHD have been reported (3). I t was found that acetylene, cyclopentadiene, cycloheptatriene, and toluene are the principal products of decoinposition. The present investigation on BCHD was undertaken to see whether acetylene and cyclopentadiene could have been formed from the valence tautomer BCI-ID[3.2.0] as follows:The decoinposition of BCHD[3.2.0] t o cycloheptatriene is linown (4). I-Iomever, BCHD[3.2.0] also could decoillpose to give cyclopentadiene and acetylene in the sanle fashion as cyclobutane con~pounds (5). I t was hoped that this study would throw soille light on the transition state involved in the decomposition of BCHD[2.2.1].BCHD[2.2.1] supplied by Chemical Internlediate and Research I,aboratories, Cuyahoga Falls, Ohio, was subjected to fractional distillation, and a middle cut was further purified by gas chromatography and found to be 99.9% pure. Cyclopeiltadiene used in the calibration of the gas chroinatograph was prepared (6) from dicyclopentadiene (Eastman Kodali Co.) and subsequently purified by gas chromatography. Acetylene (RiIatheson 99.66y0) was used without further purification, except trap-to-trap distillation, for gas chroinatographic calibration. Nitric oxide (Matheson 98.7y0) was purified by several distillations from -160 to -196'. Oxygen (Matheson 99.5y0) was used directly from the cylinder.The apparatus used and the experimental procedure were in part similar to that described previously (7). Two cylindrical reaction vessels made of pyrex were used in a vertical furnace: (a) unpacked vessel, (b) vessel paclied with thin-walled pyrex tubings to increase the surface:volurne ratio by a factor of 25.After each run the reaction mixture was coildensed out of the reaction zone into an 'Isstled as N.R. C. ATo. 8004.

show abstract

“…It is proposed that the latter mechanism accounts for the pH-independent reaction of 2methylthiazoline, by analogy to the conclusions drawn for the alkaline hydrolysis of Schiflf bases.16 This mechanism is described in eq. 3 and 4,37 where it is assumed that Áfi >> [H+], and that the reverse re-TH+ + OHproducts…”

Section: Discussionmentioning

confidence: 99%

The Effect of Structural Variation on the Hydrolysis of Δ²-Thiazolines

Schmir¹

1965

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Isomerization of Bicyclo(2.2. 1 )-2,5-heptadiene to Cycloheptatriene

Cited by 21 publications

References 4 publications

Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene

Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene

THE THERMAL UNIMOLECULAR DECOMPOSITION OF Δ^2,5-BICYCLO[2.2.1]HEPTADIENE

The Effect of Structural Variation on the Hydrolysis of Δ²-Thiazolines

Contact Info

Product

Resources

About

Isomerization of Bicyclo(2.2. 1 )-2,5-heptadiene to Cycloheptatriene

Cited by 21 publications

References 4 publications

Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene

Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene

THE THERMAL UNIMOLECULAR DECOMPOSITION OF Δ2,5-BICYCLO[2.2.1]HEPTADIENE

The Effect of Structural Variation on the Hydrolysis of Δ2-Thiazolines

Contact Info

Product

Resources

About

THE THERMAL UNIMOLECULAR DECOMPOSITION OF Δ^2,5-BICYCLO[2.2.1]HEPTADIENE

The Effect of Structural Variation on the Hydrolysis of Δ²-Thiazolines