@article {1862,
	title = {Interaction of tertiary phosphines with lignin-type, alpha,beta-unsaturated aldehydes in water},
	journal = {Inorganic Chemistry},
	volume = {46},
	number = {22},
	year = {2007},
	note = {Moiseev, Dmitry V. Patrick, Brian O. James, Brian R. Hu, Thomas Q.},
	month = {Oct},
	pages = {9389-9399},
	abstract = {To learn more about the bleaching action of pulps by (hydroxymethyl)phosphines, lignin chromophores, such as the alpha,beta-unsaturated aromatic aldehydes, sinapaldehyde, coniferylaldehyde, and coumaraldehyde, were reacted with the tertiary phosphines R2R{\textquoteright}P [R = R{\textquoteright} = Me, Et, (CH2)(3)OH, iPr, cyclo-C6H11, (CH2)(2)CN; R = Me or Et, R{\textquoteright} = Ph; R = Ph, R{\textquoteright} = Me, m-NaSO3-C6H4] in water at room temperature under argon. In all cases, initial nucleophilic attack of the phosphine occurs at the activated C=C bond to form a zwitterionic monophosphonium species. With the phosphines PR3 [R = Me, Et, (CH2)(3)OH] and with R2R{\textquoteright}P (R = Me or Et, R{\textquoteright} = Ph), the zwitterion undergoes self -condensation to give a bisphosphonium zwitterion that can react with aqueous HCI to form the corresponding dichloride salts (as a mixture of RR- and S,S-enantiomers); X-ray structures are presented for the bisphosphonium chlorides synthesized from the Et3P and Me3P reactions with sinapalclehyde. With the more bulky phosphines, iPr(3)P, MePPh2, (cyclo-C6H11)(3)P, and Na[Ph2P(m-SO3-C6H4)]b only an equilibrium of the monophosphonium zwitterion with the reactant aldehyde is observed. The weakly nucleophilic [NC(CH2)(2)](3)P does not react with sinapaldehyde. An analysis of some exceptional H-1 NMR data within the prochiral phosphorus centers of the bisphosphonium chlorides is also presented.},
	isbn = {0020-1669},
	url = {<Go to ISI>://000250345400049},
	author = {Moiseev, D. V. and Patrick, B. O. and James, Brian R. and Hu, Thomas Q.}
}
