Data Entry: Please note that the research database will be replaced by UNIverse by the end of October 2023. Please enter your data into the system https://universe-intern.unibas.ch. Thanks
An Oxidation Induced by Potassium Metal : Studies on the Anionic Cyclodehydrogenation of 1,1 `-Binaphthyl to Perylene
Journal
The journal of organic chemistry
Volume
75
Number
21
Pages / Article-Number
7358-7364
Abstract
Oxidative cyclization of 1, 1 `-binaphthyl (1) to perylene (2) can be achieved in essentially quantitative yield by the action of three or more equivalents of potassium metal in hot tetrahydrofuran. An overall reaction mechanism is proposed that accounts for all of the experimental observations reported by previous investigators and those from the present studies. The trans-6a,6b-dihydroperylene dianion (6(2-)) is believed lobe the pivotal intermediate from which H-2, is lost. A radical chain reaction involving free hydrogen atoms (H-center dot) in the two-step propagation cycle is proposed to explain the formation of H-2 from 6(2-). Anionic cyclodehydrogenations of this sort are complementary to those performed under strongly acidic/oxidizing conditions, photochemically, or thermally (flash vacuum pyrolysis), and a better understanding of how they occur, together with the optimized synthetic protocol reported here, should encourage their wider use in organic synthesis.