Studies On The Synthcsis Of Single-wing Extcnded Tribenzotriquinacenes

This thesis was devoted to the synthesis of single-wing extended tribenzotriquinacenes (TBTQs) and optical resolution of inherently chiral TBTQ-salicylic acid. It mainly consists of the following three parts:In chapter1, the methods of benzyne generation and related cycloaddition reactions were documented. In connection with our own research programme, benzyne generation from the corresponding aryl anions was emphasized. Moreover, the Diels-Alder reaction,[2+2],[3+2], and [2+2+2] cycloadditon reactions in which benzyne serving as the reactive dienophile were summarised extensively. We emphasized on the practical usefulness of benzyne in synthesis of functionalized molecules and natural products so as to inspire our further research.In chapter2, Firstly we described the generation of TBTQ-based benzyne for the first time and the corresponding trapping reactions with furans and benzyl azide. Benefitted from the high invertion-barrier of TBTQ scaffold, the related adducts of TBTQ-benzyne and furans containing the cis-and trans-isomers. Moreover, the TBTQ-based isobenzofuran was synthesized firstly and successfully trapped with various dienophiles. Among those, the intriguing results were obtained from the corresponding1,4-quinones adducts. Each of the trapping reactions delivered the syn-endo and anti-endo isomers. Following the methods used, a series of single-wing extended TBTQs which combined both convex-convave TBTQ backbone and planar naphthalene or anthracene were available. Furthermore, some "molecular tweezers" in which two TBTQs were tethered with a common rigid linkage were synthesized. Not surprisingly, both the syn-and anti-isomers were detected in case of a benzene serving as the linkage. In summary, we began with the extension of TBTQ from only one of its benzene rings and this method was especially suitable to synthesize TBTQ "suparmolecules". The effort to prepare more elaborate TBTQs may pave the way for further studies in host-guest chemsitry.In chapter3, the defination of inherently chiral molecules and their classification were depicted briefly. Futhermore, the synthesis of TBTQ-based salicyclic acid and its optical resolution via (R)-BINOL were discussed in detail. Our methods involved the separation of the diastereomers via column chromatography in stead of conventional chiral HPLC methods. After removal of the (R)-BINOL auxiliary, a pair of enantiomers were obtained and its CD spectra showed a nearly mirror image. This strategy may lay foundation for further studies in asymmetrical catalysis and chiral recognition.