Quinquearyl compound

Shibata further examined consecutive reactions of poly-ynes. When tetraynes (where two 1,6-diyne moieties were connected with a naphthalene spacer) were submitted, quinquearyl compounds with four consecutive axial chiralities were obtained (Scheme 11.15). Even an octayne proved to be a good substrate, and a noviaryl compound with eight consecutive axial chiralities was obtained in almost perfect enantioselectivity (Scheme 11.16) [23]. 

Shibata and Tsuchikama subsequently developed the enantio- and diastereoselec-tive [2 + 2 + 2] cycloaddition reactions of tetraynes with monoynes. These reactions proceeded in the presence of the same chiral iridium catalyst to give helically chiral quinquearyl compounds, possessing four consecutive axial chiralities, with perfect... 

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