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Synlett 2003(11): 1701-1703
DOI: 10.1055/s-2003-40993
LETTER
© Georg ThiemeVerlag Stuttgart ˙ New York

Stereospecific DearomatisingCyclisation of Tertiary α-Amidoorganolithiums

Jonathan Clayden*, Faye E. Knowles, Christel J. Menet
Department of Chemistry, University of Manchester, Oxford Road,Manchester M13 9PL, UK
Fax: +44(161)2754939; e-Mail: j.p.clayden@man.ac.uk;
Further Information

Publication History

Received 13 March 2003
Publication Date:
05 August 2003 (online)

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Abstract

Lithiation of benzamides derived from a chiral and enantiomericallypure α-methylbenzylamine leads to diastereoselective andregioselective dearomatising cyclisations with overall conservationof the stereochemistry of the starting stereogenic centre.

Key words

amide; - lithiation - cyclisation - stereospecificity - dearomatisation

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17

The X-ray crystal structure of a relatedcyclisation product (see ref. [26] )allows us confidence in assigning both absolute and relative stereochemistryas shown.

19

Clayden, J.; Menet, C. J. Tetrahedron Lett., inpress.