Croatica Chemica Acta, Vol. 48 No. 3, 1976.
Original scientific paper
Synthesis and Basic Hydrolysis of Diesters of a-Anilinobenzylphosphonic Acid. Conformational Study of Esters by Nuclear Magnetic Resonance Spectroscopy
V. Jagodić
; »Ruder Boskovic« Institute, 41000 Zagreb, Croatia, Yugoslavia
Abstract
Neutral esters of a-anilinobenzy1phosphonic add, R1C5H4-
NHCH(C6H4R2)PO(OR)2, (R1, R2 = H, N02, NH2, OH, COOH, Br;
R = Et, Oct.), were prepared and the influence of the substituents
on their a1kaHne hydrolysis was investigated. In most cases, even
Wiith an excess of NaOH, sodium salts of the monoesters were
formed. Exceptions were p-nitro derivatives (1, 2) where a rupfa1re
of the P-C bond took place, and a 2-hydroxybenzyl derivative (7)
which afforded disodium salt of phosphonic acid (15). The correspondin1g
monoester (21) was prepared in a high yield :£rom 7
with an equimolar amount of NaOH. The NMR spectral studies
Lndicated that the ethyl ester groups ~n neutral esters are not
equivalent. This phenomenon is discussed Ln terms of hydrogen
bonding and different conformation. A triplet was obtroned for the
CH3 group only in ethyl monoesters and their sodium salts where
a P02 - ion presumedly exists.
Keywords
Hrčak ID:
196464
URI
Publication date:
23.9.1976.
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