Abstract
Tributyltin hydride-mediated cyclisation of dehydroalanines produces an intermediate captodative radical, which can be trapped by reaction with oxygen- or carbon-centred radicals or (principally) electron-poor alkenes, to provide a quick approach to a variety of α-substituted pyroglutamates.
References
1.
(a)
Giese B.
,
Kopping B.
,
Göbel T.
,
Dickhaut J.
,
Thoma G.
,
Kulicke K. J.
, and
Trach F.
, Organic Reactions , 1996 , 48 , 301 .
2.
Aldabbagh F.
, and
Bowman W. R.
, Contemp. Org. Synth. , 1997 , 261 .
3.
Bowman W.R.
,
Bridge C. F.
, and
Brookes P.
, J. Chem. Soc., Perkin Trans. 1 , 2000 , 1 .
4.
For recent examples see: (a)
Bryans J.S.
,
Large J. M.
, and
Parsons A. F.
, J. Chem. Soc., Perkin Trans. 1 , 1999 , 2897 .
5.
Bryans J.S.
,
Large J. M.
, and
Parsons A. F.
, J. Chem. Soc., Perkin Trans. 1 , 1999 , 2905 .
6.
For recent examples see: (a)
Ishibashi H.
,
Higuchi M.
,
Ohba M.
, and
Ikeda M.
, Tetrahedron Lett. , 1998 , 39 , 75 .
7.
Ikeda M.
,
Ohtani S.
,
Yamamoto T.
,
Sato T.
, and
Ishibashi H.
, J. Chem. Soc., Perkin Trans. 1 , 1998 , 1763 .
8.
(a)
Goodall K.
, and
Parsons A. F.
, J. Chem. Soc., Perkin Trans. 1 , 1994 , 3257 .
9.
Goodall K.
, and
Parsons A. F.
, Tetrahedron , 1996 , 52 , 6739 .
10.
Baker S.R.
,
Burton K. I.
,
Parsons A. F.
,
Pons J-F.
, and
Wilson M.
, J. Chem. Soc., Perkin Trans. 1 , 1999 , 427 .
11.
Part of this work has been reported previously:
Baker S.R.
,
Parsons A. F.
, and
Wilson M.
, Tetrahedron Lett. , 1998 , 39 , 2815 .