A MOLECULAR ORBITAL CALCULATION STUDY ON RING-OPENING REACTIONS OF FLUORINE-CONTAINING 3,4-DIHYDRO-2H-PYRANS WITH AMINES AND THIOLS

作者：Ota Norio^*; Kamitori Yasuhiro; Tamai Yusuke; Feng Guo; Hatakenaka Mizuki; Okada Etsuji

来源：Heterocycles, 2011, 83(11): 2509-2516.

DOI：10.3987/COM-11-12258

• Fluorine-Containing Heterocycle
• Dihydropyran
• 1,3-Butadienylamine
• 1,3-Butadienyl Sulfide
• Molecular Orbital Calculation

The reactions of 5-trifluoroacetyl-6-trifluoromethy1-3,4-dihydro-2H-pyran (la) with various amines and sodium thiolates gave the corresponding 4,4-bistrifluoroacetyl-1,3-butadienyl amines (2b) and sulfides (2c), respectively, in good yields. Our DFT calculations suggested that the elimination of isobutanol from la and the subsequent electrocyclic ring-opening reaction on intermediate (4a) would proceed to afford 4,4-bistrifluoroacetyl-1,3-butadienyl ether (2a). Moreover, subsequent nucleophilic O-N and O-S exchange reactions on 2a which gave 2b and 2c, respectively, were also predicted.

• 出版日期2011-11-1