Diastereoisomeric atropisomers of peri-substituted naphthamides: Synthesis, stereoselectivity and stability

Tetrahedron Letters

Volumn 40, Issue 45, 1999, Pages 7883-7887

  Clayden, Jonathan ^a   Westlund, Neil ^a   Wilson, Francis X ^b  

^a UNIVERSITY OF MANCHESTER   (United Kingdom)

^b ROCHE PRODUCTS LTD   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

ALCOHOL DERIVATIVE; AMIDE; KETONE DERIVATIVE; NAPHTHALENE DERIVATIVE; ORGANOLITHIUM COMPOUND;

ARTICLE; CONFORMATION; MOLECULAR STABILITY; OXIDATION; STEREOCHEMISTRY; STEREOISOMERISM; SYNTHESIS;

EID: 0033527779     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(99)01644-5     Document Type: Article

References (11)

1. For an overview, see: Clayden, J. Synlett 1998, 810.
2. Clayden, J.; Westlund, N.; Wilson, F. X. Tetrahedron Lett. 1996, 37, 5577.
3. Ahmed, A.; Bragg, R. A.; Clayden, J.; Lai, L. W.; McCarthy, C.; Pink, J. H.; Westlund, N.; Yasin, S. A. Tetrahedron 1998, 54, 13277.
4. The closeness in space of the 1- and 8-substituents of a naphthalene means each substituent has a profound effect on the reactivity of the other. For a discussion, see: Kirby, A. J.; Percy, J. M. Tetrahedron 1988, 44, 6903 and 6911.
5. Gay, R. L.; Hauser, C. R. J. Am. Chem. Soc. 1967, 89, 2297.
6. Grierson, D. Org. Reac. 1990, 39, 85.
7. 3 (Superhydride®) gives high selectivities in the reduction of 2-acyl-1-naphthamides. See Ref. 2.
8. We were unable to do this with the amides 14a-c because in solution at room temperature (and even over a period of months as solids at -18°C) they cyclised to the lactones 18.
9. Stewart, W. H.; Siddall, T. H. Chem. Rev. 1970, 70, 517.
10. Chupp, J. P.; Olin, J. F. J. Org. Chem. 1967, 32, 2297.
11. It is quite possible that the ratios for 14 are essentially under thermodynamic control: it is noticeable that 14a, 14b, and 14c are each formed with similar stereoselectivities from two different reagents. Our assessment of the role of thermodynamic control in determining the product ratios is tentative because we have no information about the rate of epimerisation of either 14 or 15 under the conditions of the reaction - a second pathway for epimerisation could include the metal-catalysed reversible formation of 18, for example.