@article{b21608b7f8ab4d25bcc1075a5d7e7172,
title = "Duplicated ring enlargement of 4,9-methanothia[11]annulene to 6,11-methanothia[15]annulene",
abstract = "3,10-Dipyrrolidinyl-4,9-methanothia[11]annulene reacts with excess dimethyl acetylenedicarboxylate (DMAD) in refluxing toluene to give ring-enlarged 6,11-methanothia[15]annulene. X-ray crystallographic analysis of the product shows two different cis,trans-dienyl parts in the ring system. Product formation possibly involves π-facial selective addition of the enamine with DMAD and torque-selective ring opening of the intermediate cyclobutenes.",
keywords = "Cycloaddition, Electrocyclic reaction, Enamine, Methanothia-annulene, X-ray crystallographic analysis",
author = "Shigeyasu Kuroda and Rie Kasai and Ryo Nagaya and Ryuta Miyatake and Yoshikazu Horino and Naoko Matsumoto and Mitsunori Oda",
note = "Funding Information: This research was carried out in part under financial support from Kyowa Hakko Chemical Co. Inc. (for S.K.). A financial support from the Faculty of Science at Shinshu University (for M.O.) is also acknowledged. ",
year = "2011",
month = mar,
day = "30",
doi = "10.1016/j.tetlet.2010.11.072",
language = "英語",
volume = "52",
pages = "1426--1429",
journal = "Tetrahedron Letters",
issn = "0040-4039",
publisher = "Elsevier Ltd.",
number = "13",
}