Formaldoxime

Structural formula
General
Surname	Formaldoxime
other names	N -hydroxyformaldimine Formaldehyde oxime
Molecular formula	CH 3 NO
Brief description	colorless crystalline powder (trimer hydrochloride)
External identifiers / databases
CAS number 75-17-2 62479-72-5 (trimer hydrochloride) PubChem 6350 Wikidata Q1437379
properties
Molar mass	45.04 g mol −1
Physical state	firmly
Melting point	127–129 ° C (decomposition) (trimer hydrochloride)
safety instructions
GHS labeling of hazardous substances Caution H and P phrases H: 315-319-335 P: 261-305 + 351 + 338
Toxicological data	30 mg kg −1 ( LD 50 ,  rat ,  oral , trimer hydrochloride)
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Formaldoxime is the oxime of formaldehyde . It is used as a reagent for the photometric determination of manganese (II), iron (II), nickel (II), cerium (IV) and vanadium (V) ions.

Extraction and presentation

Formaldoxime solution as a reagent for photometric measurements is made from formaldehyde and hydroxylamine .

${\displaystyle \mathrm {H_{2}C{=}O+H_{2}N{-}OH\ \rightleftharpoons \ H_{2}C{=}NOH+H_{2}O.} }$

In the solid state, it is trimeric as 1,3,5-trihydroxy-1,3,5-triazacyclohexane, the hydrochloride of which is commercially available.

properties

Formaldoxime forms red-brown complexes with Mn ³⁺ and violet complexes with Fe ²⁺ .

${\displaystyle \mathrm {3H_{2}C{=}NOH+Mn^{3+}\ \rightleftharpoons \ [(H_{2}C{=}NO)_{3}Mn]+3H^{+}.} }$

use

Formaldoxime reagent is used for the determination of manganese (II). Iron (II), nickel (II), cerium (IV) and vanadium (V) can also be determined. The solution, colored by formaldoxime-metal complexes, is measured photometrically.

Individual evidence

1. ↑ ^{a b c} Data sheet formaldoxime (trimer hydrochloride) from AlfaAesar, accessed on March 17, 2010 ( PDF )(JavaScript required) .
2. ↑ ^{a b} Data sheet Formaldoxime trimer hydrochloride from Sigma-Aldrich , accessed on April 2, 2011 ( PDF ).
3. ^ E. Müller, O. Beyer, H. Meerwein, K. Ziegler (eds.): Nitrogen compounds I (=  Houben-Weyl Methods of Organic Chemistry . Volume 10 , no. 4 ). 4th edition. Georg Thieme Verlag, Stuttgart 1968, ISBN 978-3-13-210104-3 , p. 58 ( limited preview in Google Book search).