TY - JOUR
T1 - Nucleophilic reactions of 5-tert-butyl-2-methoxy-3H-azepine with alkoxides and alkyllithium reagents
AU - Kubota, Yasuhiro
AU - Satake, Kyosuke
AU - Ikui, Ryusuke
AU - Okamoto, Hideki
AU - Kimura, Masaru
PY - 2003/4
Y1 - 2003/4
N2 - The reaction of 5-tert-butyl-2-methoxy-3H-azepine (2a) with sodium alkoxides gave 2-alkoxy-3H-azepine derivatives 3-6 by nucleophilic transetherification. The treatment of 2a with tert-butyllithium also yielded 2,5-di-tert-butyl-3H-azepine (7); however, the reaction of 2a and methyllithium gave the expected 5-tert-butyl-2-methyl-3H-azepine (8) along with unexpected 5-tert-butyl-2,2-dimethyl-2,3-dihydro-1H-azepine (9), but also 5,5′-di(tert-butyl)-2,2′-methylenedi(3H-azepine) (11), the structure of which was found to be tautomerized 5-tert-butyl-2-(5-tert-butyl-2,3-dihydro-1H-azepin-2-ylidene-methyl)- 3H-azepine (12). The energy profile for the observed tautomerization is discussed based on ab initio DFT calculations and kinetic measurements.
AB - The reaction of 5-tert-butyl-2-methoxy-3H-azepine (2a) with sodium alkoxides gave 2-alkoxy-3H-azepine derivatives 3-6 by nucleophilic transetherification. The treatment of 2a with tert-butyllithium also yielded 2,5-di-tert-butyl-3H-azepine (7); however, the reaction of 2a and methyllithium gave the expected 5-tert-butyl-2-methyl-3H-azepine (8) along with unexpected 5-tert-butyl-2,2-dimethyl-2,3-dihydro-1H-azepine (9), but also 5,5′-di(tert-butyl)-2,2′-methylenedi(3H-azepine) (11), the structure of which was found to be tautomerized 5-tert-butyl-2-(5-tert-butyl-2,3-dihydro-1H-azepin-2-ylidene-methyl)- 3H-azepine (12). The energy profile for the observed tautomerization is discussed based on ab initio DFT calculations and kinetic measurements.
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U2 - 10.1246/bcsj.76.805
DO - 10.1246/bcsj.76.805
M3 - Article
AN - SCOPUS:0038336184
SN - 0009-2673
VL - 76
SP - 805
EP - 811
JO - Bulletin of the Chemical Society of Japan
JF - Bulletin of the Chemical Society of Japan
IS - 4
ER -