I. Total synthesis of (-)-cylindrocyclophane A. II. Synthesis of fluorescent reactive polymers and their applications to detection of inter-macromolecular reactions.

摘要

In part I, the total synthesis of naturally occurring C2-symmetric paracyclophane, (−)-cylindrocyclophane A, is described. Construction of the macrocyclic backbone was accomplished by a double Horner-Emmons macrocyclic dimerization reaction with high E/Z selectivity. The monomer for this dimerization has been prepared in 16 steps starting from 4-bromo-3,5-dimethoxybenzylalcohol. The configuration of the butyl-containing benzylic stereocenter was established by tandem enzymatic resolution of allylic alcohol followed by Ireland-Claisen rearrangement. Conversion of the ester groups in macrocyclic dimer to methyl groups and the derivative of cylindrocyclophane A, the structure of which was secured by a single X-ray analysis. A remarkable deprotection of the four aryl methyl ethers with excess methylmagnesium iodide at 160°C cleanly provided (−)-cylindrocyclophane A.; In part II synthesis of fluorescent reactive polymers and their applications to detection of inter-macromolecular reactions are described. Several ways to make reactive polymers with fluorescence groups are developed. Anionic polymerization and/or atom transfer radical polymerization (ATRP) were the main tools to prepare the polymers with controlled molecular weights and architecture. These polymers have been used to monitor the reactions between two reactive polymers at the interface in polymer blending at high dilution limits. Also, several approaches to achieve fluorogenic reactive polymers were studied.