N-(Diphenylmethylene)methanamine

(R = H)

[13280-16-5]  · C14H13N  · N-(Diphenylmethylene)methanamine  · (MW 195.28) (R = Li)

[64042-43-9]  · C14H12LiN  · 1,1-Diphenyl-2-azaallyllithium  · (MW 201.21)

(lithiation produces an a-amino carbanion equivalent)

Alternate Names: benzophenone N-methylimine; N-(diphenylmethylene)methylamine.

Preparative Methods: prepared by condensation of benzophenone with methylamine in the presence of TiCl41 or by various other methods.2,3

Amine Synthesis by Reaction of 2-Azaallyl Anions with Electrophiles.4,5

The benzophenone imine of methylamine is deprotonated to a 2-azaallyl anion which reacts with electrophiles (alkyl halides, epoxides, aldehydes, and ketones)6-9 at the methylene terminus. Hydrolysis yields nucleophilic aminomethylation products derived from a synthetic equivalent of the a-carbanion of a primary amine (eq 1).

Interesting derivatives of silicon, germanium, and tin (Ph2C=N-CH2SiR3, Ph2C=N-CH2GeR3, and Ph2C=N-CH2SnR3) have been prepared by lithium-metal exchange.10 Reaction with cyclic carbamates followed by hydrolysis has been reported (eq 2).11,12

Other Reactions.

Various cycloaddition reactions ([2 + 2];13-16 [2 + 2 + 2];13-15 [3 + 2];17,18 [4 + 2];19 [6 + 3-]20) of either the neutral parent or anionic derivative have been reported. Reaction with the chromium carbene complex [(CO)5Cr=C(OMe)Me] under photochemical conditions gives a b-lactam by a formal [2 + 2] cycloaddition.21

The parent Schiff base has also served as the electrophile for reaction with n-Butyllithium22 or an active methylene compound.23 Orthometalation by reaction with Tin(IV) Chloride,24 as well as oxidation to either oxaziridine or nitrone,25-27 has been reported.

Related Reagents.

Benzophenone Imine; N-t-Butoxycarbonyl-N-methylaminomethyllithium; Dimethylaminomethyllithium; N-(Diphenylmethylene)aminoacetonitrile; Ethyl N-(Diphenylmethylene)glycinate; N-t-Butyl-N-methyl-N-trimethylsilylmethylformamidine; Nitromethane; N-Nitrosodimethylamine.


1. Moretti, I.; Torre, G. S 1970, 141.
2. Morimoto, T.; Sekiya, M. CL 1985, 1371.
3. Feringa, B. L.; Jansen, J. F. G. A. TL 1986, 27, 507.
4. For reviews, see: (a) Kauffmann, T. AG(E) 1974, 13, 627; (b) Beak, P.; Zajdel, W. J.; Reitz, D. B. CRV 1984, 84, 471.
5. For synthetic studies with various related systems, see: (a) Arrowsmith, J. E.; Cook, M. J.; Hardstone, D. J. JCS(P1) 1979, 2364; (b) Tsuge, O.; Ueno, K.; Kanemasa, S.; Yorozu, K. BCJ 1987, 60, 3347; (c) Pearson, W. H.; Szura, D. P.; Harter, W. G. TL 1988, 29, 761; (d) Hornback, J. M.; Murugaveri, B. TL 1989, 30, 5853.
6. Kauffmann, T.; Köppelmann, E.; Berg, H. AG(E) 1970, 9, 163.
7. Cuvigny, T.; Hullot, P. CR(C) 1971, 272, 862.
8. Hullot, P.; Cuvigny, T. BSF 1973, 2989.
9. Kauffmann, T.; Berg, H.; Köppelmann, E.; Kuhlmann, D. CB 1977, 110, 2659.
10. Popowski, E.; Hahn, A.; Kelling, H. JOM 1976, 110, 295.
11. Schubert, J.; Schwesinger, R.; Prinzbach, H. AG(E) 1984, 23, 167.
12. Schubert, J.; Schwesinger, R.; Knothe, L.; Prinzbach, H. LA 1986, 2009.
13. Schaumann, E. CB 1976, 109, 906.
14. Schaumann, E.; Mrotzek, H. CB 1978, 111, 661.
15. Schaumann, E.; Ehlers, J.; Grabley, F.-F. CB 1980, 113, 3010.
16. Goerdeler, J.; Ho, C.-h. CB 1983, 116, 1297.
17. Kauffmann, T.; Eidenschink, R. CB 1977, 110, 645.
18. Kauffmann, T.; Ahlers, H.; Echsler, K.-J.; Schulz, H.; Tilhard, H.-J. CB 1985, 118, 4496.
19. Cushman, M.; Gentry, J.; Dekow, F. W. JOC 1977, 42, 1111.
20. Bower, D. J.; Howden, M. E. H. JCS(P1) 1980, 672.
21. Hegedus, L. S.; McGuire, M. A.; Schultze, L. M.; Chen, Y.; Anderson, O. P. JACS 1984, 106, 2680.
22. Hu, L.; Mauze, B.; Miginiac, L. CR(C) 1977, 284, 195.
23. Ivanova, G. G. T 1992, 48, 177.
24. Clegg, W.; Grievson, C. M. J.; Wade, K. CC 1987, 969.
25. Forni, A.; Moretti, I.; Torre, G. CC 1977, 731.
26. Bucciarelli, M.; Forni, A.; Moretti, I.; Torre, G. JCS(P1) 1980, 2152.
27. Boyd, D. R.; Coulter, P. B.; McGuckin, M. R.; Sharma, N. D.; Jennings, W. B.; Wilson, V. E. JCS(P1) 1990, 301.

Martin J. O'Donnell

Indiana University-Purdue University at Indianapolis, IN, USA



Copyright 1995-2000 by John Wiley & Sons, Ltd. All rights reserved.