Spiro hydrocarbons and dibenzo[c,p]chrysene from 1-tetralone

Abstract

very slow induced decomposition of cumene hydroperoxide was reported to occur with AIBN.19 Competitive Reactions.-Competitive autoxidations were carried out with an equimolar mixture of two substituted isopropylbenzenes (each ca. 1.2-0.6 M ) in chlorobenzene at 60' in the presence of AIBN (0.26-0.09 M ) . Aliquots (each 1 ml) were taken out at appropriate intervals of time and reduced with 15% KSH in aqueous methanol. After completion of reduction, the solution was washed with water, extracted with two 4-ml portions of chloroform, and analyzed by means of glpc. The products were analyzed by a Yanagimoto gas chromatograph with a flame ionization detector, Model GCG-%OF, employing (19) J. A. Howard and K. U. Ingold, Can. J . Chem., 46, 2655 (1968). a 1.0 m X 2.5 mm column packed with Apiezon Grease (5%) on Chamelite CS of 80-100 mesh using NS as a carrier gas at 160-220'. The internal standards for glpc were nitrobenzene for cumene and m-diisopropylbenzene for isopropylcumyl hydroperoxide End isopropylcumyl alcohol. The relative rate constants of competitive oxidation were calculated from the equation k = km/k, = log [ ( b -y)/b]/log[(a -%)/a]. Here, a and b are initial concentrations of substrates and 5 and y are corresponding concentrations a t time t.Acknowledgment. -The authors wish to thank Dr. RII. Yamashita for his helpful advice in performing these experiments.

Synthesis and Characterization of Pyridine‐, Pyrazine‐, and Quinoxaline‐Derived [4]Helicenes and S‐Shaped Double [4]Helicenes

“…Isomeric 1‐aza[4]helicenes (only two of them are known) are rare. [16b], There is also little known about double [4]carbohelicenes (dibenzo[ c , p ]chrysenes),[21a], [21b] and their aza‐analogues are unknown. Recently, double S‐shaped aza[4]helicenes (phenanthridino[10,9‐ k ]phenanthridines) have been synthesized by a metal‐free C(sp 3 )–H amination reaction with unprotected anilines.…”

“…Recently, double S‐shaped aza[4]helicenes (phenanthridino[10,9‐ k ]phenanthridines) have been synthesized by a metal‐free C(sp 3 )–H amination reaction with unprotected anilines. [21c]…”

Photochemistry of aromatic compounds. Internal return in the photosolvolysis of 3,5-dimethoxybenzyl acetate

“…Journal of the American Chemical Society / 97:4 / February °Atom % excess lsO at ether position, 7.36 ± 0.08%. 6 Analyses by mass spectrometry; footnote 9a.c By combined NMR and GLPC analyses. d For run 3, a trace of 9 and an unidentified compound (0.3%) were detected also. '…”

Convenient Syntheses of Dibenzo[c,p]chrysene and Its Possible Proximate and Ultimate Carcinogens: In Vitro Metabolism and DNA Adduction Studies

“…A synthesis of DB[ c,p ]C has been reported in the literature starting from self-condensation of tetralone via a spiral intermediate . However, this method cannot be applied to the syntheses of fjord region dihydrodiol metabolites of DB[ c,p ]C. We intended to exploit the Suzuki cross-coupling approach for their syntheses.…”