A new phosphorylating reagent. II. Preparation of mixed diesters of phosphoric acid by the use of alkyl 2-chloromethyl-4-nitrophenyl hydrogen phosphates

Synthetic studies on phosphorylating reagent. II. 2-(N,N-Dialkylamino)-4-nitrophenyl phosphate and its use in the synthesis of phosphate esters

“…Recently, with a view to developing a milder reagent which could be used in the phosphorylation of amino alcohols, the reactivity of the inner salt of l-(2-dihydrogenphosphoroxy-5-nitrobenzyl)pyridinium hydroxide (3) was investigated.1 This reagent derived from 1 showed reduced activity and reacted satisfactorily with a tert-amino substituted alcohol to afford the teri-aminoalkyl phosphate. However, phosphorylation of alcohols which have secondary and primary amino groups resulted in the unfavorable formation of the phosphoroamidate.…”

“…Alkylation of 4 with 2.5 molar quantities of methyl or ethyl iodide in the presence of tri- 2-( , -Dialky lamino)-4-nitrophenyl Phosphate Figure 1. The yield of benzyl dihydrogen phosphate with time, in the reaction of benzyl alcohol (equimolar quantity) with phosphorylating reagents: a, 2-(/V, N-dimethy lamino) -4-nitrophenyI phosphate (6a); b, 2-(JV,iV-diethylamino)-4-nitrophenyl phosphate (6b); c, inner salt of iV-(2-dihydrogen phosphoroxy-5-nitrobenzyl)pyridinium hydroxide (3).…”