{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T14:00:24Z","timestamp":1753884024814},"reference-count":15,"publisher":"CLOCKSS Archive","issue":"9","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["HETEROCYCLES"],"published-print":{"date-parts":[[2005]]},"DOI":"10.3987\/com-05-10482","type":"journal-article","created":{"date-parts":[[2009,2,17]],"date-time":"2009-02-17T08:32:10Z","timestamp":1234859530000},"page":"2139","source":"Crossref","is-referenced-by-count":3,"title":["Acid Catalyzed Cyclization Reaction of 3-Hydrazono-1,1,1-trifluoro-2-alkanones to 6-Trifluoromethyl-3,6-dihydro-2H-[1,3,4]oxadiazines"],"prefix":"10.13030","volume":"65","author":[{"given":"Yasuhiro","family":"Kamitori","sequence":"first","affiliation":[]},{"given":"Tomoko","family":"Sekiyama","sequence":"additional","affiliation":[]}],"member":"5187","reference":[{"key":"10.3987\/COM-05-10482-1","unstructured":"1. Y. Kamitori, M. Hojo, R. Masuda, T. Fujitani, S. Ohara, and T. Yokoyama, Synthesis, 1988, 208."},{"key":"10.3987\/COM-05-10482-2","doi-asserted-by":"crossref","unstructured":"2. Y. Kamitori, M. Hojo, R. Masuda, S. Ohara, K. Kawasaki, and Y. Kawamura, Synthesis, 1990, 493.","DOI":"10.1055\/s-1990-26916"},{"key":"10.3987\/COM-05-10482-3","doi-asserted-by":"crossref","unstructured":"3. Y. Kamitori, M. Hojo, R. Masuda, T. Fujitani, S. Ohara, and T. Yokoyama, J. Org. Chem., 1988, 53, 129; Y. Kamitori, M. Hojo, R. Masuda, T. Yoshida, S. Ohara, K. Yamada, and T. Yokoyama, J. Org. Chem., 1988, 53, 519.","DOI":"10.1021\/jo00236a026"},{"key":"10.3987\/COM-05-10482-4","unstructured":"4. R. S. Mulliken, J. Chem. Phys., 1955, 23, 1833, 1841, 2338, 2343."},{"key":"10.3987\/COM-05-10482-5","unstructured":"5. Y. Kamitori, M. Hojo, and T. Yoshioka, Heterocycles, 1998, 48, 2221."},{"key":"10.3987\/COM-05-10482-6","unstructured":"6. On the basis of our calculations (RMP2\/6-31G*), oxadiazine tautomer (9) is estimated as 15.0 Kcal\/mol less stable than 2 (R= H). Such tautomer like 9 could not be detected in any experiment we examined so far using hydrazones (1)."},{"key":"10.3987\/COM-05-10482-7","doi-asserted-by":"crossref","unstructured":"7. B. K. Carpenter, Tetrahedron, 1978, 34, 1877, and references cited therein.","DOI":"10.1016\/0040-4020(78)80091-X"},{"key":"10.3987\/COM-05-10482-8","unstructured":"8. The difference of \u0394H between the reaction from 18 to 19 and that from 4\u2019 to 9 is thought to be mainly owing to the instability of 4\u2019 compared to 18. Electron-withdrawing CF3 group is directly attached to the cation conjugate system on 4\u2019, whereas CH3 hyperconjugation should stabilize cation (18) effectively. The following proton exchange reaction is 8.1 Kcal\/mol exothermic (RB3LYP\/6-31G*\/\/ RB3LYP\/6-31G*). Such substituent effects should be insignificant for intermediates 9 and 13."},{"key":"10.3987\/COM-05-10482-9","unstructured":"9. Larger resonance energy expected in oxadiazine (17) in comparison with 16 should be the main reason why 16 could not be isolated at all. Semi-empirical PM3 calculations suggest that 17 is about 0.8 Kcal\/mol more stable than 16."},{"key":"10.3987\/COM-05-10482-10","unstructured":"10. Wavefunction, Inc."},{"key":"10.3987\/COM-05-10482-11","unstructured":"11. A. D. Becke, J. Chem. Phys., 1993, 98, 5648."},{"key":"10.3987\/COM-05-10482-12","unstructured":"12. W. J. Hehre, L. Radom, P. v. R. Schleyer, and J. A. Pople, \u2018Ab Initio Molecular Orbital Theory,\u2019 Wiley, Inc., New York, 1986."},{"key":"10.3987\/COM-05-10482-13","doi-asserted-by":"crossref","unstructured":"13. M. Clark, R. D. Cramer III, and N. van Opdensch, J. Computational Chem., 1989, 10, 982.","DOI":"10.1002\/jcc.540100804"},{"key":"10.3987\/COM-05-10482-14","unstructured":"14. J. J. P. Stewart, J. Computer Aided Molecular Design, 1992, 6, 69."},{"key":"10.3987\/COM-05-10482-15","unstructured":"15. 1H NMR (CDCl3) \u03b4 1.13 (s, 9H, tert-Bu), 2.45 (s, 3H, NCH3), 6.97-7.87 (m, 10H, C6H5)."}],"container-title":["HETEROCYCLES"],"original-title":[],"language":"en","deposited":{"date-parts":[[2024,6,24]],"date-time":"2024-06-24T20:41:16Z","timestamp":1719261676000},"score":1,"resource":{"primary":{"URL":"https:\/\/triggered.stanford.clockss.org\/ServeContent?doi=10.3987%2Fcom-05-10482"},"secondary":[{"URL":"https:\/\/triggered.edinburgh.clockss.org\/ServeContent?doi=10.3987%2Fcom-05-10482","label":"edinburgh"}]},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2005]]},"references-count":15,"journal-issue":{"issue":"9","published-print":{"date-parts":[[2005]]}},"alternative-id":["COM-05-10482"],"URL":"https:\/\/doi.org\/10.3987\/com-05-10482","relation":{},"ISSN":["0385-5414"],"issn-type":[{"type":"print","value":"0385-5414"}],"subject":[],"published":{"date-parts":[[2005]]}}}