Synthesis of racemic 1,2,3,4-tetrahydroisoquinolines and their resolution
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1-Aniline-substituted 3,4-dihydroisoquinolines were obtained in various ways using the Bischler-Napieralski reaction. The effect of the protecting group at the aniline nitrogen atom on the course of the reaction has been studied and it was found that the N-phthalyl group was stable under the cyclization conditions. The dihydroisoquinolines were reduced to the racemic 1,2,3,4-tetrahydroisoquinolines which were resolved by crystallization of the diastereomeric tartrates. Two examples of 1,2,3,4-tetrahydroisoquinolines were obtained in optically pure form (>99%ee).
Keywordsdihydroisoquinolines 1,2,3,4-isoquinolines resolution of isomeric tartrates
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- 1.M. D. Razwadowska,Heterocycles,39, 903 (1944).Google Scholar
- 5.E. Vedejs, A. W. Kruger, and E. Suna,J. Org. Chem.,64, 783 (1999).Google Scholar
- 8.B. Wünsch and S. Nerdinger,Eur. J. Org. Chem., No. 2, 513 (1999).Google Scholar
- 9.S. Doi, N. Shirai, Y. Sato,J. Chem. Soc., Perkin Trans. I, No. 15, 2217 (1997).Google Scholar
- 11.S. Nagubandi and G. Fodor,J. Heterocycl. Chem.,17, 1457 (1980).Google Scholar
- 20.P. Newman,Optical Resolution Procedures for Chemical Compounds. Amines and Related Compounds. Riverdale, New York, 1984.Google Scholar
- 21.H. Ott, US Pat 3297696;Chem. Abstr.,66, 65505 (1967).Google Scholar
- 22.B. Love,Can. J. Chem.,42, 1488 (1964).Google Scholar
- 23.G. Palazzo and B. Silvestrini, US Pat 3409668;Chem. Abstr.,70, 37496 (1969).Google Scholar