Diethyl phosphoramidate

The high reactivity of N-H bonds has also been exploited to produce N-F denvatives without significant substitution on neighbonng C-H bonds, Diethyl-phosphoramidates of ammonia, alkylammes, and a,polar solvents to produce difluoroamine [57], N,N-difluoroalkylamines, and a,to-bis(At,7V-difluoroamino)alkanes [52] Acetamide undergoes fluonnation to give modest yields of N,N difluoroacetatnide and acetyl fluonde when fluorinated... 

Gaseous ammonia reacted with the phosphorochloridate at 0° producing solid diethyl phosphoramidate in accordance with the equation Et,PO,a+2NH, = Et POjNH4+NH C1. 

Scheme 6.12 Synthesis of azacyclophanes by -alkylation of diethyl phosphoramidates.38...

In contrast to the anion of diethyl phosphoramidate or trifluoromethanesulfonamide, which cannot be cleanly monoalkylated, - the anion of trifluoroacetamide (100) was monoalkylated by alkyl halides or alkyl methanesulfonate. The resulting A -alkylamides (101) were converted into primary amines by alkaline hydrolysis or reduction (NuBHa Scheme 42). Various primary amines were prepared from (100) with primary alkyl iodides or methanesulfonate, benzyl and allyl halides, a-bromocarbonyl compounds and 2,4-dinitrochlorobenzene. However, competitive elimination is a serious side reaction for less reactive primary alkyl chlorides and secondary halides or methanesulfonate. The synthesis of secondary amines from (100) has also been reported. ... 

The first attempt to prepare dialkyl 1-aIkynyIphosphonates by a Michaelis-Becker reaction was reported in 1965, " Only octyne is produced when 1-bromooctyne is allowed to react with sodium diethyl phosphite in liquid ammonia, the coproduct being diethyl phosphoramidate. It seems likely that reduction of the bromo compound occurs by a halogen-metal exchange, with the resulting diethyl bromophosphate being immediately converted into diethyl phosphoramidate by the hquid anunonia. ... 

Two phosphoramidates newly employed for the preparation of pure amines, are diethyl A -trimethylsilylphosphoramidate and diethyl A -t-butoxycarbonyl-phosphoramidate/ each of which is initially converted into its anion which, in turn, is alkylated in the presence of tetrabutylammonium bromide, deprotected, and acidolysed to give the primary amine. In another modification (Scheme 13) the addition of diethyl phosphoramidate to an alkene occurs in the presence of mercuric nitrate, and acidolysis of the product again gives a pure primary amine. ... 

Nitrosoalkanes condense with diethyl phosphoramidate in the presence of Bu OCl, A/ -bromosuccinimide, or more particularly, of dibromoisocyanurate, to give (diethoxyphosphinoyl)diazene oxides it is thought that this reaction proceeds through the... 

The same phosphazo-phosphonyl compound MeONP2Cl4 results from the reaction of either phosphorus pentachloride and ethyl P-methyl phosphon-amidate or methyltetrachlorophosphorane and diethyl phosphoramidate (EtO)2P(0)NH2, and although the structure could not be determined by chemical means, formula (80) rather than the isomeric (81) is suggested by C1 n.q.r. measurements. ... 

Photocatalytic activity has also been observed with some of these compounds. For instance, titanium dioxide nanoparticles were able to degrade 2-chloroethyl sulfide (mustard) in liquid and gas phase, a series of warfare agents like diethyl sulfide, dimethyl methyl phosphonate, diethyl phosphoramidate, pinacolyl methyl-phosphonate, and butylaminoethanthiol, and pesticides such as lindane, methyl parathion, and dichlorvos upon exposure to ultraviolet light (Vigo and Thibodeaux, 2001 Sundarrajan et al., 2010). Zinc oxide nanoparticles were incorporated into polymers used to produce electrospun coating on cotton fabrics and provided them with photocatalytic-activated antimicrobial properties (Munoz-BonUla and Femandez-Garcia, 2012). 

Scheme 3 Synthesis of polyazacyclophanes via N-alkylation of diethyl phosphoramidates.

Typical procedure. Diethoxyphosphinyl isocyanate diethyl phosphorocyanatidate) [350] A solution of diethyl phosphoramidate (30.6 g, 0.2 mol) in tetrachloro-methane (50 mL) was slowly added dropwise with stirring and effident external cooling to a solution of oxalyl chloride (27.9 g, 0.22 mol) in the same solvent (150 mL). The reaction temperature was kept at —5 to 0 °C. After completion of the addition, the temperature of the mixture was slowly increased to 50 °C and this was maintained for 1 h. The mixture was then cooled to room temperature, filtered, and concentrated in vacuo. The residual liquid product was distilled in vacuo (bp 85-87 °C/10 Torr) yield 22.9 g (64%). 

Diethyl phosphoramidate heated with trimethylsilyl-N,N-diethylamine in benzene under anhydrous conditions with distillation of benzene and diethylamine where-... 

Together with R. rhodochrous ATCC 21197 [43] and Pseudomonas putida NRRL 18668 [51], also Rhodococcus sp. C3II md Rhodococcus erythropolis MP 50 were used for the enantiospecific preparation of (S)-naproxen [65]. Rhodococcus sp. C3II lacks a nitrilase but exhibits nitrile hydratase and amidase activities, both of which are constitutive and prefer the (5 )-enantiomers of naproxen derivatives. On the other hand, the enzymes from R. erythropolis MP 50 were induced by nitriles and its nitrile hydratase was (R)-specific [44]. Due to the presence of a strictly (5)-specific amidase, both strains finally formed (5)-naproxen with high enantioselectivity (Fig. 18). Evidence for the enantioselectivity of the nitrile hydratases of both strains was obtained by the formation of optically active amides in the presence of the amidase inhibitor diethyl phosphoramidate [63,65]. The nitrile hydratase of Rhodococcus sp. C3II whole cells was used for the sjmthesis of (>S)-naproxen amide with 94% e.e. after 30% conversion in the presence of the amidase inhibitor [63]. In addition, the highly stereoselective amidases of these two strains were used to prepare (5)-ketoprofen (Fig. 28), and the amidase from R. erythropolis MP 50 was used to prepare (5)-2-phenylpropionic acid with more than 99% e.e. and more than 49% conversion [66,67]. 

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