Mehmet YILMAZ, Emre BİÇER and A. Tarık PEKEL

Manganese(III) Acetate Mediated Free Radical Cyclization of 1,3-Dicarbonyl Compounds with Sterically Hindered Olefins

The manganese(III) acetate mediated radical cyclization of dimedone 1a, 2,4-pentanedione 1b, ethyl acetoacetate 1c, 1,3-cyclohexanedione 1d and 5-phenyl-1,3-cyclohexanedione 1e with 1,1-diphenyl-1-butene 2a afforded 4,5-dihydrofurans (3c, 3e) and tetrahydrobenzofurans (3a, 3g, 3h) in good yields (55% - 77%). Additionally, the reactions of trifluoromethyl-group containing 1,3-dicarbonyls, 4,4,4-trifluoro-1-phenylbutane-1,3-dione 1f and 4,4,4-trifluoro-1-thien-2ylbutane-1,3-dione 1g with 2a 3-trifluoroacetyl-4,5-dihydrofurans gave in 74% and 78% yields, respectively. Treatment of 1a, 1b and 1c with 1,2-diphenyl-1-pentene 2a resulted in the formation of tetrahydrobenzofuran 3b and 4,5-dihydrofurans 3d and 3f in lower yields.

Anahtar Kelimeler:

Manganese(III) acetate, free radical cyclization, 1, 3-dicarbonyl, 4, 5-dihydrofuran, tetrahydrobenzofuran, trifluoroacetyl, oxidative addition

Manganese(III) Acetate Mediated Free Radical Cyclization of 1,3-Dicarbonyl Compounds with Sterically Hindered Olefins

Keywords:

Manganese(III) acetate, free radical cyclization, 1, 3-dicarbonyl, 4, 5-dihydrofuran, tetrahydrobenzofuran, trifluoroacetyl, oxidative addition,

PDF

___

H.B. Kagan and J.L. Namy, Tetrahedron 42, 6573-6614 (1986).
G.A. Molander, Chem. Rev. 92, 29-68 (1992).
J. Igbal, B. Bhatia and N.K. Nayar, Chem. Rev. 94, 519-64 (1994).
G.G. Melikyan, A.B. Sargsyan and Sh.O. Badanyan, Chem. Heterocyclic Comp. 606-9 (1989).
E.J. Corey and A.K. Ghosh, Chem. Lett. 223-26 (1987).
M. Yılmaz and A.T. Pekel, Synthetic Comm. 31, 3871-76 (2001).
J.M. Mellor and S. Mohammed, Tetrahedron Lett. 32, 7111-14 (1991).
J.M. Mellor and S. Mohammed, Tetrahedron 49, 7547-56 (1993).
S. Kajikawa, H. Nishino and K. Kurosawa, Heterocycles 54, 171-83 (2001).
R. Fujino, H. Nishino, Synthesis 731-40 (2005).
G.G. Melikyan, Synthesis 833-50 (1993).
B.B. Snider, Chem Rev., 96 339-63 (1996).
D. Yang, X. Ye, S. Gu and X. Ming, J. Am. Chem. Soc. 121, 5579-80 (1999).
B.B. Snider, J.Y. Kiselgof and B.M. Foxman, J. Org. Chem. 63, 7945-52 (1998).
B.B. Snider, L. Han and C. Xie, J. Org. Chem. 62, 6978-84 (1997).
M.E. Kurz, P. Ngoviwatchai and T. Tantrarant, J. Org. Chem. 46, 4668-72 (1981).
A. Citerio, R. Santi, T. Fiorani and S. Strologo, J. Org. Chem. 54, 2703-12 (1989).
A.S. Demir and A. Jeganathan, Synthesis 235-47 (1992).
A.S. Demir, H. Akg¨un, C. Tanyeli, T. Sayrac and D.S. Watt, Synthesis 719-21 (1991).
N.K. Dunlap, M.R. Sabol and D.S. Watt, Tetrahedron Lett. 25, 5839-42 (1984).
A.S. Demir and A. Saatcioglu, Synthetic Comm. 23, 571-75 (1993).
A.S. Demir, ¨O. Reis and A.C. Igdir, Tetrahedron 60, 3427-32 (2004).
A.S. Demir, ¨O. Reis and M. Emrullaho˘glu, Tetrahedron 58, 8055-58 (2002).
A.S. Demir, ¨O. Reis and M. Emrullaho˘glu, J. Org. Chem. 68, 578-80 (2003).
A.S. Demir, ¨O. Reis and E. ¨Ozg¨ul-Karaaslan, J. Chem. Soc., Perkin Trans. 1, 3042-45 (2001).
M. Yılmaz and A.T. Pekel, Synthetic Comm. 31, 2189-94 (2001).
M. Yılmaz and A.T. Pekel, J. Fluorine Chem. 126, 401-06 (2005).
B.B. Snider, J.J. Patricia and S.A. Kates, J. Org. Chem. 53, 2137-43 (1988).
C.M. Hill, R.A. Walker, M.E. Hill, J. Am. Chem. Soc. 73, 1663-64 (1951).
A. Guvenc, A.T. Pekel and O.M. Kockar, Chem. Engineering J. 99, 257-63 (2004).
S. Kimitaka and A. Kiichi, Nippon Kaguku Zasshi 89, 1110-13 (1968), CA: 70, 86838 (1970).