Browse by author
Lookup NU author(s): Dr Simon DohertyORCiD, Dr Julian Knight, Thomas Scanlan, Dr Mark Elsegood, Professor William Clegg
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
The aprotic and protic bi- and multidentate iminophosphines 2-Ph2PC6H4N=CR1R2 (R1 = H, R2 = Ph = 2a; R1 = Me R2 = Ph = 2b; R1 = H, R2 = 2-thienyl = 2c; R1 = H, R2 = C6H4-2-PPh2 = 2d; R1 = H, R2 = C6H4-2-OH = 2e, R1 + H,R2 = C6H4-2-OH-3Bu′ = 2f: R1 = H, R2 = CH2C(O)Me = 2g) have been prepared by the acid catalyzed condensation of 2-(diphenylphosphino)aniline with the corresponding aldehyde-ketone. Iminophosphine 2d can be reduced with sodium cyanoborohydride to give the corresponding amino-diphosphine has been characterized by single-crystal X-ray crystallography, as its palladium dichloride derivative. The attempted condensation of 2-(diphenylphosphino)aniline with pyridine-2-carboxaldehyde to give the corresponding pyridine-functionalized iminophosphine resulted in an unusual transformation involving the diastereoselective addition of two equivalents of aldehyde to give 1,2-dipyridin-2-yl-2-(o-diphenylphosphinoyl) phenylamino-ethanol, which has been characterized by a single-crystal X-ray structure determination. The bidentate iminosphosphine 2-Ph2PC6H4N=C(H)Ph reacts with [(cycloocta-1,5-diene)PdCIX] X = Cl. Me) to give [Pd 2- Ph2PC6H4N-C(H)Ph|CIX] and the imino-diphosphine 2-Ph2PC6H4N=C(H)C6H4-PPh2 reacts with [(cycloocta-1,5-diene)PdClMe] to give [Pd|2-Ph2PC6H4N=C(H)C6H4-PPh2}ClMe] and each has been characterized by single-crystal X-ray crystallography. The monobasic iminophosphine 2-Ph2PC6H4N=C(Me)CH2C(O)Me reacts with [Ni(PPh3)2Cl2] in the presence of NaH to give the phosphino-ketoiminate complex [Ni{2-Ph2PC6H4N=C(Me)CHC(O)Me}Cl], which has been structurally characterized. Mixtures of iminophosphines 2a-h and a palladium source catalyze the Suzuki cross coupling of 4-bromoacetophenone with phenyl boronic acid. The efficiency of these catalysts show a marked dependence on the palladium source, catalysts formed from [Pd2(OAc)6 giving consistently higher conversions than those formed from [Pd2(dba)3] and [PdCl2(MeCN)2]. Catalysts formed from neutral bi- and terdentate iminophosphines 2a-d gave significantly higher conversions than those formed from their monobasic counterparts 2e-f. Notably, under our conditions the conversions obtained with 2a-c compare favorably with those palladium. In addition, mixtures of [Ir(COD)Cl]2 and 2a-h are active for the hydrosilytation of acetophenone; in this case catalysts formed from monobasic iminophosphines 2e-f giving the highest conversions. © 2002 Elsevier Science B.V. All rights reserved.
Author(s): Doherty S, Knight JG, Scanlan TH, Elsegood MRJ, Clegg W
Publication type: Review
Publication status: Published
Journal: Journal of Organometallic Chemistry
Year: 2002
Volume: 650
Issue: 1-2
Pages: 231-248
ISSN (print): 0022-328X
ISSN (electronic): 1872-8561
URL: http://dx.doi.org/10.1016/S0022-328X(02)01203-2
DOI: 10.1016/S0022-328X(02)01203-2
