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has been cited by the following article:

• TITLE: Synthesis and Conformational Studies of Some Metacyclophane Compounds

  AUTHORS: Louis Korbla Doamekpor, Vincent Kodzo Nartey, Raphael Kwaku Klake, Takehiko Yamato

  KEYWORDS: Metacyclophanes; Calixarenes; Cone; Partial-Cone; Conformers; Variable Temperature Proton Nuclear Magnetic Resonance Spectroscopy; Coalescence Temperature

  JOURNAL NAME: International Journal of Organic Chemistry, Vol.2 No.2, June 28, 2012

  ABSTRACT: Various [3.3.3]metacyclophane derivatives were synthesized from 6,15,24-tri-tert-butyl-9,18,27-trimethoxy [3.3.3] metacyclophane-2,11,20-trione 1 using simple chemical reactions. The conformations of the synthesized compounds were studied using mainly solution Proton Nuclear Magnetic Resonance (1H NMR) spectroscopic methods. Two of the synthesized compounds 5, 6, were found to have a partial cone conformation with the third, 4, having the cone conformation. Detailed variable temperature Proton Nuclear Magnetic Resonance studies further confirmed the partialcone conformation for the two products, 5, 6. During the variable temperature nuclear magnetic resonance spectroscopic studies, 6,15,24-tri-tert-butyl-9,18,27-trimethoxy[3.3.3]metacyclophane-2,11,20-triol was found to have a coalescence temperature of about 0?C.