Diphenylphosphinyl Chloride Research Articles

A study on the selective phosphorylation and phosphinylation of hydroxyphenols

AbstractBy choice of appropriate reaction conditions, the phosphorylation of hydroquinone by diethyl chlorophosphate gave predominantly the monophosphate (2). A similar reaction of phloroglucinol led to the mixture of the possible products (6, 7, and 8). The monophosphinylation of the above hydroxyphenols by diphenylphosphinyl chloride could be accomplished with a good selectivity to give product 4 or 9, the yields, however, being variable. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:126–130, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10006

Synthesis of dipeptide 4-nitroanilides containing non-proteinogenic amino acids.

A series of tert-butyloxycarbonyl amino acid 4-nitroanilides, including N-alkylated amino acids and (R)-thiazolidine-4-carboxylic acid, (S)-oxazolidine-4-carboxylic acid. (4S,5S)-5-methyloxazolidine-4-carboxylic acid, (4S,5R)-5-methyloxazolidine-4-carboxylic acid, (S)-azetidine-2-carboxylic acid, (S)-pipecolic acid and (S)-3,4-dehydroproline, were prepared conveniently by the isocyanate method or the mixed anhydride procedure. The resulting amino acid 4-nitroanilides were extended to corresponding dipeptide 4-nitroanilides with tert-butyloxycarbonyl-(S)-alanine. In the case of sterically hindered amino acid 4-nitroanilides the mixed anhydride procedure with diphenylphosphinyl chloride was successful.

Precolumn derivatization of retinoic acid for liquid chromatography with fluorescence and coulometric detection

Derivatization of the carboxyl function of retinoic acid by fluorescent or electroactive reagents prior to liquid chromatography was studied. Ferrocenylethylamine was synthesized and could be coupled to retinoic acid. The coupling reaction involved activation by diphenylphosphinyl chloride. The reaction was carried out at ambient temperature in 50 min with a yield of ca. 95%. The derivative can be detected by coulometric reduction (+100 mV) after on-line coulemetric oxidation (+400 mV). The limit of detection was 1 pmol of derivative on-column, injected in a volume of 10 μl, but the limit of quantification was 10 pmol of retinoic acid.

Quantification of the enantiomers of ofloxacin in biological fluids by high-performance liquid chromatography

Two methods for the determination of (+)- and (−)-ofloxacin in biological fluids by high-performance liquid chromatography are described. The first method is separation on a chiral stationary phase with bovine serum albumin immobilized on silica gel. The second is the coupling of ofloxacin to l-leucinamide via diphenylphosphinyl chloride activation. The diastereoisomeric derivatives are then separated on a common reversed-phase column. The second method revealed only slight differences in the pharmacokinetics of (+)- and (−)-ofloxacin in humans after an intravenous administration of racemic ofloxacin.

Radiation mechanisms. Part II. Electron spin resonance studies of the mechanism of radiation processes in trivalent phosphorus derivatives

A range of phosphites (trimethyl phosphite, trimethyl and tripropyl thiophosphite, di-isopropylphosphinyl chloride, diphenylphosphinyl chloride, and dithioethylphosphinyl chloride) have been exposed, either pure or in a range of solvents, to 60Co γ-rays at 77 K. The radical products have been analysed by e.s.r. spectroscopy. We conclude that, after electron addition, the radical anions may protonate on phosphorus, lose an anionic ligand to give a phosphinyl radical or lose a neutral ligand (alkyl, alkoxy, thiyl or chlorine radicals). These radicals may subsequently add to adjacent molecules to give a range of phosphoranyl species. It is also suggested that the primary anion may sometimes rearrange to give an alkylphosphoranyl radical directly.

Metal Phosphinylides and Phosphinothioylides. I. Formation of Metal Diphenylphosphinylides and Diphenylphosphinothioylides and the Reactions with Some Organic Halides and Aldehydes

Abstract Lithium diphenylphosphinylide or diphenylphosphinothioylide ([Ph2PX]Li; X=O, S), prepared from diphenylphosphine oxide or sulfide and n-butyllithium, reacted with methyl iodide, acetaldehyde and benzaldehyde to give the corresponding phosphine oxides or sulfides in good yields, indicating the formation of C–P bond. Formation of [Ph2PS]MgCl from diphenylphosphinothioyl chloride (1) and magnesium was confirmed by the similar reactions. When 1 was allowed to react with magnesium or sodium for a long time, diphenylphosphides ([Ph2P]M) were produced by desulfurization, together with [Ph2PS]M (M=MgCl, Na). Reaction of 1 with [Ph2PS]M gave tetraphenyldiphosphine disulfide through formation of P-P bond, while diphenylphosphinyl chloride and [Ph2PO]M reacted through formation of P–O bond. The difference has been explained by soft-hard-acid-base concept.