Stereoselective Iterative Convergent Synthesis of Z-Oligodiacetylenes from Propargylic Dithioacetals.
A series of (t)Bu-substituted Z-oligodiacetylenes (Z-ODAs) are synthesized from the reactions of allenyl/propargylic zinc reagents, obtained from the corresponding propargylic dithiolanes and BuLi, with dithiolane-substituted propargylic aldehydes followed by stereospecific elimination of β-thioalkoxy alcohols under Mitsunobu conditions. The stereochemical assignments are based on NOE experiments. The X-ray structure of the hexamer further supports the Z configuration for each of the double bonds in these ODAs. The photophysical properties of these Z-ODAs have been examined and are compared with known related E- and Z-ODAs with different substituents.
Department of Chemistry, National Taiwan University , Taipei 106, Taiwan.
Chih-Wei
CW
Chen
Department of Chemistry, National Taiwan University , Taipei 106, Taiwan.|Department of Chemistry, University of Science and Technology of China , Hefei, Anhui 230026, China.
Kunzeng
K
Fan
Department of Chemical Engineering, Feng Chia University , Taichung 407, Taiwan.
Chih-Hsien
CH
Chen
Department of Chemistry, National Taiwan University , Taipei 106, Taiwan.
Shou-Ling
SL
Huang
Department of Chemistry, National Taiwan University , Taipei 106, Taiwan.
Yi-Hung
YH
Liu
Department of Physics, Tung Hai University , Taichung 407, Taiwan.
Tsong-Shin
TS
Lim
Department of Chemistry, University of Science and Technology of China , Hefei, Anhui 230026, China.
Guan-Wu
GW
Wang
Department of Chemistry, National Taiwan University , Taipei 106, Taiwan.
Tien-Yau
TY
Luh