Diethylphosphoryl cyanide

Diethylphosphoryl cyanide 3 as a reagent lor amide bond lormation and applicallon to peptide synthesis tree ol racemization. 

N-Benzoyl L-leucylglyclne ethyl ester (3). N-Benzoy-L-leucine 1 (0.235 g, 1 mmol) and glycine ethyl ester hydrochloride 2 (0 1534 g, 1.1 mmol) in OMF (10 mL) under stirring vyas treated with diethylphosphoryl cyanide 3 (0.179 g, 1.1 mmol) In OMF at 0°C, followed by the addition of triethylamine (0.212 g, 2 1 mmoO. The mixture was stirred for 30 min at 0°C and 4 h at 20 C The reaction mixture was diluted with PhH-EtOAc, washed with 5% HCI, water, 5% NaHCOs solution and bnne. Evaporation of the solvent gave crude 4 which after sIDca gel chromatography afforded 0.271 g of 4 (66%) (pure L), mp 1S8-160°C. 

Diethyl phthalate Diethyl pyrocarbonate Diethylphosphoryl cyanide Di(2-ethylhexyl)phosphoric acid Diethyl sucdnylsuccinate Diethyl tartrate Drisopropyl fluorophosphate... 

Diethylphosphoryl cyanide 3 a reagent for amide bond formation and application to peptide synthesis free of racemization (see 1st edition). 

Diethyl cyanophosphonate is also known as diethylphosphoryl cyanide, diethoxy-phosphoryl cyanide, diethylphosphorocyanidate, diethyl cyanophosphate, and DEPC.13 It can be readily prepared from triethyl phosphite and cyanogen bromide.2 It is very toxic and corrosive and it must be handled in a fame hood. The reagent is moisture sensitive and should be stored under nitrogen in a refrigerator. 

In connection with synthesis of quinomycin model systems, Chen and Olsen found that diethylphosphoryl cyanide is the reagent of choice for coupling amino acid derivatives to cis- or rra/ 5-4-aminocyclohexanecarboxylic acid. Other procedures, including the carbodiimide, p-nitrophenyl active ester, and symmetrical anhydride methods, were less satisfactory. 

AMIDES Boron tribromide. Boron trifluoride etherate. 6-Chloro-l-p-chlorobenzene-sulfonyloxybenzotriazole. Diethylphosphoryl cyanide. Dihalobis(triphenylphosphine)-palladium(H). Dihalobis(triphenylphosphine)paUadium(ll) complexes. Palla-dium(II) chloride. Sodium amide. Trimethylsilyl isocyanate. Triphenylphosphine ditriflate. 

Derivatives of phosphoric acid, diphenylphosphoryl azide (72) (DPPA) [123], diethylphosphoryl cyanide (73) (DEPC) [124], bis(2-oxo-... 

Shiori and co-workers used 5-substituted 4-oxazolecarboxylic acid esters 379 as p-hydroxy-a-amino acid synthons. They described a straightforward synthesis of 379 by acylation of an isocyanoacetic acid ester with an a-alkoxyacid 378 in the presence of diphenylphosphorylazide (DPPA) or diethylphosphoryl cyanide (DPPC) followed by base-catalyzed cyclization (Scheme 1.104). The reaction conditions do not epimerize optically active a-alkoxyacids. Dilute acid hydrolysis of 379 and reaction with (600)2 affords the protected aminotetronic acids 380. Stereoselective hydrogenation of 380 then yields the 1,4-lactones 381, key intermediates in the synthesis of amino sugars. A variety of a-alkoxyacids were studied, and some examples are shown in Table 1.30. 

Me and rhodamine B (Rh B) were incorporated into polyethyleneimine and PVA by using diethylphosphoryl cyanide or l-methyl-2-chloropyridinium iodide as the coupling agent The SnOj coated with these films exhibited remarkably sensitized... 

Abbreviations CDMT = 2-chloro-4,6-dimethoxy-l,3,5-triazine EDCI = l-ethyl-3-(3-dimethyla-minopropyl)carbodiimide BOP = benzotriazol-l-yloxy-tris-(dimethylamino)phosphonium hexa-fluorophosphate DIPEA = diisopropylethylamine DEPC = diethylphosphoryl cyanide CBM IT = l,l-carbonylbis(3-methylimidazolium triflate HOBt = 1-hydroxybenzotriazole hydrate HBPyU = 0-(benzotriazole-l-yl)-iV,Af,A,Af-bis(tetramethylene)uronium hexafluorophosphate. 

Dichloro-5,6-dicyano-l,4-benzoquinone diethylphosphoryl cyanide deactivation factor 2-Deoxy-ara >/no-hexose Diisobutylaluminumhydride... 

The nitrile is reduced to the aldehyde using diisobutylaluminum hydride. Subsequent cyanohydrin synthesis using diethylphosphoryl cyanide provides the starting material for the next substitution step. Thus, with each step, nucleophiles can be... 

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