Diastereoselective addition of allylzinc bromide to imines derived from (R)-phenylglycine amide van der Sluis, Marcel ; Dalmolen, J; de Lange, B; Kaptein, B; Kellogg, RM; Broxterman, QB; Broxterman, Quirinus B. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum.
ABSTRACTThe highly diastereoselective addition of allylzinc bromide to imines derived from (R)-phenylglycine amide is reported. Homoallylamines with high enantiomeric purity are obtained from the adducts in three steps on removal of the chiral auxiliary by means of a nonreductive protocol. Removal of the auxiliary by hydrogenation leads to the saturated amines, also in high enantiomeric purity.Chiral homoallylamines are valuable synthons for the preparation of topically interesting compounds such as -amino acids, 1,3-amino alcohols, and 1-amino-3,4-epoxides. 1 Recently, 2,3 homoallylamines proved to be key building blocks for the preparation of some pyrrolidines and piperidines via the ring-closing metathesis approach. The most frequently employed methodology for the synthesis of homoallylamines is the allylation of imines by allyl Si, Sn, Sm, Li, Mg, Zn, Ce, Cr, B, or Cr reagents. 4 High 1,3-asymmetric induction during the addition can be achieved by using imines derived from chiral auxiliaries such as R-arylethylamines, 5 -amino alcohols, -alkoxy amines, and R-amino acid esters. 6 A common feature of the latter three auxiliaries is the presence of a second heteroatom, which is capable of rigidifying the transition state of the 1,2- Org. Chem. 1999, 64, 4233. (d) Nakamura, K.; Yamamoto, Y. J. Org. Chem. 1999, 64, 2614. (e) Nakamura, H.; Nakamura, K.; Yamamoto, Y. J. Am. Chem. Soc. 1998, 120, 4242. (f) Yamamoto, Y.; Asao, N. Chem. ReV. 1993, 93, 2207
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