Electron Paramagnetic Resonance and Mass Spectroscopy Study of Spin-Trapped Radicals: Styrene

Abstract

The free radical intermediates from the photolysis of eleven substituted styrenes (1–11) with both tertiary and secondary amines were studied by spin trapping and the high-pressure liquid chromatography electron paramagnetic resonance (HPLC-EPR) technique. Eleven α-methylbenzyl radicals were trapped by 2-methyl-2-nitro-sopropane (MNP) and separated by HPLC. Resolution enhancement was applied to obtain long-range hyperfine splitting constants (hfsc). The nitrogen hfsc are linearly correlated with the Hammett substituent constants. The major mass spectral fragments for the trapped aminoxyl radicals (12–22) include [M+1]⁺, [M–1]⁺, [M–^tBu]⁺, [M–^tBuOH]⁺, [M–^tBuNO]⁺, and [(CH₃)₃C]⁺. The structures of 12–22 were also confirmed by chemical synthesis by adding Grignard reagent to α-phenyl-N-tert-butylnitrone (PBN) and its derivatives.

Keywords

Electron paramagnetic resonance (EPR)Mass spectra Spin trapping

Get full access to this article

View all access options for this article.

References

Lyons

A. L.

Jr. Turro

N. J.

, J. Am. Chem. Soc. 100, 3177 (1978).

Brentnall

R. L.

Crosby

P. M.

Salisbury

, J. Chem. Soc. Perkin Trans. 2 2002 (1977).

Cookson

R. C.

De B. Costa

S. M.

Hudec

, J. Chem. Soc. Chem. Commun. 753 (1969).

Lewis

F. D.

Reddy

G. D.

Schneider

Gahr

, J. Am. Chem. Soc. 113, 3498 (1991).

Susumu

Hida

Takamuku

Sakurai

, Nippon Kagaku Kaishi 1, 152 (1984).

Janzen

E. G.

, Acc. Chem. Res. 4, 31 (1971).

Perkins

M. J.

, in Advances in Physical Organic Chemistry, Gold

Bethel

, Eds. (Academic Press, New York, 1980), vol. 17, p. 1.

Janzen

E. G.

Blackburn

B. J.

, J. Am. Chem. Soc. 90, 5909 (1968).

Chalfont

G. R.

Perkins

M. J.

Horsfield

, J. Am. Chem. Soc. 90, 7141 (1968).

10.

Lagercrantz

Forschult

, Nature 218, 1247 (1968).

11.

Leaver

I. H.

Ramsay

G. C.

, Tetrahedron 25, 5669 (1969).

12.

Lagercrantz

, J. Am. Chem. Soc. 95, 220 (1973).

13.

Janzen

E. G.

Blackburn

B. J.

, J. Am. Chem. Soc. 91, 4481 (1969).

14.

Rosenthal

Mossoba

M. M.

Riesz

, Can. J. Chem. 60, 1486 (1982).

15.

Evans

J. C.

Jackson

S. K.

Rowlands

C. C.

, Tetrahedron 41, 5195 (1985).

16.

Janzen

E. G.

Krygsman

P. H.

Lindsay

D. A.

Haire

D. L.

, J. Am. Chem. Soc. 112, 8279 (1990).

17.

Janzen

E. G.

Weber

J. K.

Haire

D. L.

Fung

D. F.

, Anal. Lett. 18 (A14), 1749 (1985).

18.

Makino

Moryia

Hatano

, J. Chromatogr. 332, 71 (1985).

19.

Janzen

E. G.

Krygsman

P. H.

Haire

D. L.

, Biomed. Environ. Mass Spectrom. 15, 111 (1988).

20.

Abe

Suezawa

Hirota

Ishii

, J. Chem. Soc. Perkin Trans. 2 29 (1984).

21.

Krygsman

P. H.

Janzen

E. G.

Towner

R. A.

Haire

D. L.

, Anal. Lett. 22 (4), 1009 (1989).

22.

Suezawa

Abe

Hirota

Ishii

, Chem. Lett. 1049 (1981).

23.

Hedberg

Ehrenberg

, J. Chem. Phys. 48, 4822 (1969).

24.

Shimokoshi

Jones

R. N.

, J. Appl. Spectrosc. 31, 67 (1983).

25.

T.-I.

Nozaki

Naito

Okazaki

Hatano

, J. Chem. Soc. Chem. Commun. 206 (1989).

26.

Lin

C.-R.

Wang

C.-N.

T.-I.

, J. Org. Chem. 56, 5025 (1991).

27.

Vedije

Meier

G. P.

Snoble

K. A. J.

, J. Am. Chem. Soc. 103, 2823 (1981).

28.

Stowell

J. C.

, J. Org. Chem. 36, 3055 (1971).

29.

Haire

D. L.

Oehler

U. M.

Krygsman

P. H.

Janzen

E. G.

, J. Org. Chem. 53, 4535 (1988).

30.

Janzen

E. G.

Oehler

U. M.

Haire

D. L.

Kotake

, J. Am. Chem. Soc. 108, 6858 (1986).

31.

Church

D. F.

, J. Org. Chem. 51, 1138 (1986).

32.

Janzen

E. G.

, Acc. Chem. Res. 2, 279 (1969).

33.

Janzen

E. G.

Lin

C.-R.

Hinton

R. D.

, J. Org. Chem. 57, 1633 (1992).

34.

Heller

McConnell

H. M.

, J. Chem. Phys. 32, 1535 (1960).

Electron Paramagnetic Resonance and Mass Spectroscopy Study of Spin-Trapped Radicals: Styrene—Amine Photoreactions

Abstract

Keywords

Get full access to this article

References