title: Equatorenes: synthesis and properties of chiral naphthalene, phenanthrene, chrysene, and pyrene possessing bis(1-adamantyl) groups at the peri-position.
abstract: Chiral polycyclic aromatic hydrocarbons containing bis(1-adamantyl) groups at the peri-positions, named equatorenes, were synthesized in optically pure form starting from optically pure 4,5-bis(1-adamantyl)-8-methoxy-1-naphthol. A sequential Diels-Alder reaction of furan and arynes generated from 1,2-bromotriflates provided tricyclic and tetracyclic epoxides, and acid-catalyzed aromatization gave phenanthrol and chrysenol. Deoxygenation reactions involving the hydrogenolysis of triflates gave 1,8-bis(1-adamantyl)naphthalene, 1,10-bis(1-adamantyl)phenanthrene, and 1,12-bis(1-adamantyl)chrysene. 3,4-Bis(1-adamantyl)pyrene was synthesized from phenanthrol by Sonogashira coupling and Pt-catalyzed cyclization. Essentially no racemization occurred during the synthesis. X-ray analysis indicated the distorted naphthalene moiety possessing the peri-diadamantyl groups and the flat structure of the other benzene rings. UV-vis analysis of the equatorenes showed considerable redshifts compared with that of the corresponding achiral arenes. Electrochemical analysis of the naphthalene and pyrene indicated that the distortion decreased the highest occupied molecular orbital stability with no marked effect on the lowest unoccupied molecular orbital energy level, and the origin was discussed on the basis of calculation results.
authors.affiliation: Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University , Aoba, Sendai, 980-8578, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Naohiro
authors.initials: N
authors.lastname: Oyamada
authors.forename: Sheng
authors.initials: S
authors.lastname: Xia
authors.forename: Yuta
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Yamaguchi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Maeda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishihara
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Uchimaru
authors.forename: Eunsang
authors.initials: E
authors.lastname: Kwon
mesh_terms: D000218:Adamantane / Q000737:chemistry*; D002911:Chrysenes / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000138:chemical synthesis / Q000737:chemistry*; D010616:Phenanthrenes / Q000138:chemical synthesis / Q000737:chemistry*; D011721:Pyrenes / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D002911:Chrysenes; D009281:Naphthalenes; D010616:Phenanthrenes; D011721:Pyrenes; C031180:chrysene; C031721:naphthalene; C031181:phenanthrene; C030984:pyrene; D000218:Adamantane