Benzophenone imine

Benzophenone imine
Names
	Preferred IUPAC name Diphenylmethanimine
Identifiers
CAS Number	1013-88-3;
3D model (JSmol)	Interactive image;
ChemSpider	120561;
ECHA InfoCard	100.103.715
EC Number	600-205-0; 440-870-2;
PubChem CID	136809;
UNII	EJJ21NA7VI;
CompTox Dashboard (EPA)	DTXSID10870832 ;
	InChI InChI=1S/C13H11N/c14-13(11-7-3-1-4-8-11)12-9-5-2-6-10-12/h1-10,14H Key: SXZIXHOMFPUIRK-UHFFFAOYSA-N;
	SMILES C1=CC=C(C=C1)C(=N)C2=CC=CC=C2;
Properties
Chemical formula	C13H11N
Molar mass	181.238 g·mol−1
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Benzophenone imine is an organic compound with the formula of (C₆H₅)₂C=NH. A pale yellow liquid, benzophenone imine is used as a reagent in organic synthesis.^[1]

Synthesis

Benzophenone imine can be prepared by the thermal decomposition of benzophenone oxime:^[2]

2 (C₆H₅)₂C=NOH → (C₆H₅)₂C=NH + (C₆H₅)₂C=O

Benzophenone imine can also be synthesized by addition of phenylmagnesium bromide to benzonitrile followed by careful hydrolysis (lest the imine be hydrolyzed):^[3]

C₆H₅CN + C₆H₅MgBr → (C₆H₅)₂C=NMgBr

(C₆H₅)₂C=NMgBr + H₂O → (C₆H₅)₂C=NH + MgBr(OH)

This method is known as Moureu-Mignonac ketimine synthesis.^[4] Yet another route to benzophenone imine involves reaction of benzophenone and ammonia.^[5]

Reactions

Benzophenone imine undergoes deprotonation with alkyl lithium reagents.^[6]

(C₆H₅)₂C=NH + CH₃Li → (C₆H₅)₂C=NLi + CH₄

(C₆H₅)₂C=NLi + CH₃I → (C₆H₅)₂C=NCH₃ + LiI

Primary amines can be protected as benzophenone imines, and the protected amines are stable in flash chromatography.^[7]

Buchwald-Hartwig amination involves coupling aromatic halide and amine to form carbon-nitrogen bonds with the help of palladium-based catalysts. Benzophenone imine can be used as an ammonia-equivalent in such reactions.^[1]

References

^ ^a ^b Wolfe, John P.; Åhman, Jens; Sadighi, Joseph P.; Singer, Robert A.; Buchwald, Stephen L. (1997-09-08). "An Ammonia Equivalent for the Palladium-Catalyzed Amination of Aryl Halides and Triflates". Tetrahedron Letters. 38 (36): 6367–6370. doi:10.1016/S0040-4039(97)01465-2. ISSN 0040-4039.
^ Arthur Lachman (1930). "Diphenylmethane Imine Hydrochloride". Organic Syntheses. 10: 28. doi:10.15227/orgsyn.010.0028.
^ Pickard, P. L.; Tolbert, T. L. (December 1961). "An Improved Method of Ketimine Synthesis". The Journal of Organic Chemistry. 26 (12): 4886–4888. doi:10.1021/jo01070a025. ISSN 0022-3263.
^ "Moureau-Mignonac Ketimine Synthesis". Hoboken, NJ, USA: John Wiley & Sons, Inc. 2010-09-15. pp. 1988–1990. doi:10.1002/9780470638859.conrr446. ISBN 9780470638859. {{cite book}}: |journal= ignored (help); Missing or empty |title= (help)
^ Verardo, G.; Giumanini, A. G.; Strazzolini, P.; Poiana, M. (1988). "Ketimines From Ketones and Ammonia". Synthetic Communications. 18 (13): 1501–1511. doi:10.1080/00397918808081307.
^ Nottingham, Chris; Lloyd-Jones, Guy C. (2018). "Trimethylsilyldiazo[13C]methane: A Versatile ¹³C-Labelling Reagent". Organic Syntheses. 95: 374–402. doi:10.15227/orgsyn.095.0374. hdl:20.500.11820/c801073c-6b4b-4a85-be68-2c4313b6e53d.
^ O'Donnell, Martin J. (2001-04-15). "Benzophenone Imine". Chichester, UK: John Wiley & Sons, Ltd. doi:10.1002/047084289x.rb031. ISBN 978-0471936237. {{cite book}}: |journal= ignored (help); Missing or empty |title= (help)

[:2-1] Wolfe, John P.; Åhman, Jens; Sadighi, Joseph P.; Singer, Robert A.; Buchwald, Stephen L. (1997-09-08). "An Ammonia Equivalent for the Palladium-Catalyzed Amination of Aryl Halides and Triflates". Tetrahedron Letters. 38 (36): 6367–6370. doi:10.1016/S0040-4039(97)01465-2. ISSN 0040-4039.

[2] Arthur Lachman (1930). "Diphenylmethane Imine Hydrochloride". Organic Syntheses. 10: 28. doi:10.15227/orgsyn.010.0028.

[:0-3] Pickard, P. L.; Tolbert, T. L. (December 1961). "An Improved Method of Ketimine Synthesis". The Journal of Organic Chemistry. 26 (12): 4886–4888. doi:10.1021/jo01070a025. ISSN 0022-3263.

[4] "Moureau-Mignonac Ketimine Synthesis". Hoboken, NJ, USA: John Wiley & Sons, Inc. 2010-09-15. pp. 1988–1990. doi:10.1002/9780470638859.conrr446. ISBN 9780470638859. {{cite book}}: |journal= ignored (help); Missing or empty |title= (help)

[5] Verardo, G.; Giumanini, A. G.; Strazzolini, P.; Poiana, M. (1988). "Ketimines From Ketones and Ammonia". Synthetic Communications. 18 (13): 1501–1511. doi:10.1080/00397918808081307.

[6] Nottingham, Chris; Lloyd-Jones, Guy C. (2018). "Trimethylsilyldiazo[13C]methane: A Versatile ¹³C-Labelling Reagent". Organic Syntheses. 95: 374–402. doi:10.15227/orgsyn.095.0374. hdl:20.500.11820/c801073c-6b4b-4a85-be68-2c4313b6e53d.

[7] O'Donnell, Martin J. (2001-04-15). "Benzophenone Imine". Chichester, UK: John Wiley & Sons, Ltd. doi:10.1002/047084289x.rb031. ISBN 978-0471936237. {{cite book}}: |journal= ignored (help); Missing or empty |title= (help)

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