Synthesen aminosubstituierter Phosphonsäure‐ und Diphosphonsäureester

Abstract

Benziminoäthyläther ergibt mit überschüssigem Diäthylphosphit in einer Additions‐Eliminierungs‐Reaktion α‐Amino‐benzal‐diphosphonsäure‐tetraäthylester (V); das entsprechende α‐Anilino‐Derivat IX wurde aus N‐Phenyl‐benzimidchlorid in zwei Stufen erhalten. — Die Anlagerung von Diäthylphosphit an Hydramide und anschließende Verseifung der Reaktionsprodukte erbrachte eine neue Synthese für α‐Amino‐benzyl‐phosphonsäuren (XIV) und ihre Ester.

Optimization, Continuation and Lack of the One-Step Diphosphorylation Reaction. Assay of Modification of the Tetraethyl(pyrrolidine-2,2-diyl)bisphosphonate

“…INSERT SCHEME 4 By applying our procedure to 2-pyrrolidinone in the presence of one equivalent of P(OEt) 3 and one equivalent of P(OiPr) 3 , a mixture of three products 2, 15 and 16 is obtained (SCHEME 5). Unexpectedly, 25 %-25 %-50 % proportions have been measured by 31 P NMR and HPLC analysis instead of the expected 33 %-33 %-33 % ratios. Considering that the distillation treatment failed, a pure sample of compound 16 was only achieved by a preparative HPLC.…”

“…29, 30 Unfortunately most of them are quite awkward to perform and require several steps. 1,11,[31][32][33] In 1994, Yokomatsu et al were the first to describe an easy single step synthesis by a Beckmann rearrangement of oximes reagents (SCHEME 1 -Equation (1)). 15 However we failed to extend this method to a five-membered ring bisphosphonate and found at least seven products by 31 P NMR in the crude reaction with only 10 % of the target bisphosphonate.…”

“…1,11,[31][32][33] In 1994, Yokomatsu et al were the first to describe an easy single step synthesis by a Beckmann rearrangement of oximes reagents (SCHEME 1 -Equation (1)). 15 However we failed to extend this method to a five-membered ring bisphosphonate and found at least seven products by 31 P NMR in the crude reaction with only 10 % of the target bisphosphonate. 28 In 1997 and 1999, Qian et al detailed a one pot but intricate two steps procedure involving Vilsmeier reagents and organophophorus compounds with P-H bounds (SCHEME 1-Equation (2)).…”

“…Nevertheless the latter can be attained by the Kreutzkamp synthesis. 31 It is likely that the high electronegativity of the fluorine prevents the Nbenzyltrifluoroactamide from reacting (compound 13).…”

Organophosphorus Complexones

“…This procedure, suggested by Pudovik 105 " 107 , has been applied mainly to aromatic carbonyl compounds and amines, because of the ease with which the corresponding Schiff bases can be obtained 108 The interaction of phosphorous and hypophosphorous esters with alkoxyalkylamines or substituted methylenediamines yields respectively substituted aminoalkylphosphonic 91 and bisaminoalkylphosphinic ne esters:…”