7 5 S Y N T H E S I S A N D R I N G - C H A I N T A U T O M E R I S M O F S T E R E O I S O M E R S
U - O X A Z 1 N E S C O N D E N S E D W I T H A / - B U T Y L - S U B S T I T U T E D C Y C L O P E N T A N E R I N G .
Gábor Bernáth, Ferenc Fülöp, Roland Spitzner, Jorrna Mattinen+, Kalevi Pihlaja4 Institute of Pharmaceutical Chemistry, Albeit Szent-Györgyi Medical University, Eötvös u. 6, H-6720 Szeged, Hungary, " D e p a r t m e n t of Chemistry, University of Turku, SF-20500 T u r k u , Finland
In a recent comparative study of aiicydic fused tetrahydro-13-oxazines1, we have found that the 2-aryl substituent has a characteristic effect on the ring-chain tautomerism. Earlier results2 were utilized to prepare new stereoisomeric r-butyl- cyciopentane 1,3-aminoalcohols 1 and 2.
+CQ
YH XH X = NH. Y = 0 = 1
X = 0 . Y = NH : 2 X = NH. Y = 0 : 3A X = 0. Y= NH = AA
^ II
HKCY +CC
n = c /3 8
Z 3 p N O j . mCl. H, p M e . pOMe. p H M e2
Through the condensation of stereoisomeric 1,3-aminoalcohols 1 and 2 wiih aromatic aldehydes, tautomeric mixtures of 1,3-oxazines (3A and 4A) and Schiff bases (3B ana 4B) were obtained.
Tne effects of regio- and stereoisomerism, aromatic substituents and the r-butyl substituent will he analvsed.
lF. Fülöp. K. Pihlaia, J. Mattinen, G. Bernáth, / Org. Client. 52. 3821 (1987V Tetrahedron 43. 1863 (I9S7).
2G. Bemáth. M. Svoboda. Tetrahedron 2S. 5475 (1972).