Optional ortho and lateral lithiations of 4,4-dimethyl-2-(o-tolyl)oxazolines

Tetrahedron Letters

Volumn 43, Issue 50, 2002, Pages 9069-9072

  Tahara, Naruki ^a   Fukuda, Tsutomu ^a   Iwao, Masatomo ^a  

^a NAGASAKI UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

4,4 DIMETHYL 2 (O TOLYL)OXAZOLINE; ETHER DERIVATIVE; OXAZOLINE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHEMICAL PARAMETERS; CHEMICAL PROCEDURES; LITHIATION; TEMPERATURE;

EID: 0037049179     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(02)02318-3     Document Type: Article

References (23)

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9. For examples of the reagent-controlled optional regioselective lithiations; see: (a) Katsoulos, G.; Takagishi, S.; Schlosser, M. Synlett 1991, 731; (b) Shimano, M.; Meyers, A. I. J. Am. Chem. Soc. 1994, 116, 10815; (c) Maggi, R.; Schlosser, M. J. Org. Chem. 1996, 61, 5430; (d) Schlosser, M.; Maccaroni, P.; Marzi, E. Tetrahedron 1998, 54, 2763; (e) Fukuda, T.; Mine, Y.; Iwao, M. Tetrahedron 2001, 57, 975.
10. For examples of the reagent-controlled optional regioselective lithiations; see: (a) Katsoulos, G.; Takagishi, S.; Schlosser, M. Synlett 1991, 731; (b) Shimano, M.; Meyers, A. I. J. Am. Chem. Soc. 1994, 116, 10815; (c) Maggi, R.; Schlosser, M. J. Org. Chem. 1996, 61, 5430; (d) Schlosser, M.; Maccaroni, P.; Marzi, E. Tetrahedron 1998, 54, 2763; (e) Fukuda, T.; Mine, Y.; Iwao, M. Tetrahedron 2001, 57, 975.
11. For examples of the reagent-controlled optional regioselective lithiations; see: (a) Katsoulos, G.; Takagishi, S.; Schlosser, M. Synlett 1991, 731; (b) Shimano, M.; Meyers, A. I. J. Am. Chem. Soc. 1994, 116, 10815; (c) Maggi, R.; Schlosser, M. J. Org. Chem. 1996, 61, 5430; (d) Schlosser, M.; Maccaroni, P.; Marzi, E. Tetrahedron 1998, 54, 2763; (e) Fukuda, T.; Mine, Y.; Iwao, M. Tetrahedron 2001, 57, 975.
12. For examples of the reagent-controlled optional regioselective lithiations; see: (a) Katsoulos, G.; Takagishi, S.; Schlosser, M. Synlett 1991, 731; (b) Shimano, M.; Meyers, A. I. J. Am. Chem. Soc. 1994, 116, 10815; (c) Maggi, R.; Schlosser, M. J. Org. Chem. 1996, 61, 5430; (d) Schlosser, M.; Maccaroni, P.; Marzi, E. Tetrahedron 1998, 54, 2763; (e) Fukuda, T.; Mine, Y.; Iwao, M. Tetrahedron 2001, 57, 975.
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23. Schleyer has carried out theoretical studies on the directed lithiations of ortho-substituted toluenes and concluded that the preferred site for lithiation is governed by the stabilization of the transition state, rather than by the initial complexation, see: Kremer, T.; Junge, M.; Schleyer, P. v. R. Organometallics 1996, 15, 3345. Ab initio calculations of the transition structures for ortho and lateral lithiations of 1 are in progress in our laboratories.