Energetische untersuchungen zum mills—nixon-effekt

Spectrofluorometric Studies. XI. Some Aspects of the Photochemistry of Ortho-fused Benzocycloalkenes

“…The solution spectra in the first absorption region were in agreement with absorptivity measurements reported by Moore er at. (13,14), as noted in a previous publication (1 5).…”

“…On the other hand benzocycloheptene provides an interesting anomaly. It has previously been noted (13,14) that the maximum molar absorbancy index of benzocyloheptene solutions in cyclohexane is an exception to a generally decreasing trend of maximum absorbancy indices with increasing ring size. However, this is not observed in gas phase spectra (15), suggesting some type of specific interaction with the solvent.…”

Isolation of intermediates in the dicobalt octacarbonyl-catalyzed cyclotrimerization of cyclooctyne. Crystal and molecular structure of a cobaltacyclopentadiene complex

“…Caled for C24H36: C, 88.81; H, 11.19. Found: C,88.95; H, 11.08. Elution with benzene gave two bands, the faster moving of which afforded yellow plates identified as bis(hexamethylene)-l,4-benzoquinone, [C8H12CO]2 (0.045 g, 5%): mp 148-149 °C (lit.13 mp 148 °C); IR (Nujol) 1640 cm"1 MC=0)] (lit.13 1640 cm"1); mass spectrum m/e (relative intensity) 274 (67), 272 (100), 244 (10), 229 (14), 216 (9), 215 (10), 203 (12), 201 (9), 189 (12), 187 (14), 175 (13), 173 (11), 161 (14), 159 (10), 147 (9), 145 (10), 131 (11), 117 (12), 105 (18), 91 (59), 79 (30), 77 (34). Anal.…”

Ring-closure reactions. 8. Synthesis and ultraviolet spectra of macrocyclic aromatic ethers

“…The observed effect has been explained on the basis of strain on the -electron sextet both in the ground and excited state. 13 It is thus concluded that the d values reported in Table II are probably not meaningful as such, but should rather be regarded as providing a rough indication of steric hindrance to coplanarity in the various ring compounds.…”