Premium
Lithium Aluminum Hydride Assay Suitable for the Organic Chemistry Laboratory
Author(s) -
Levinger Shlomo,
Hirsch Shira,
Albeck Am
Publication year - 2016
Publication title -
chemistryselect
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 34
ISSN - 2365-6549
DOI - 10.1002/slct.201600195
Subject(s) - reagent , lithium (medication) , chemistry , aluminum hydride , hydride , boron , aluminium , alcohol , inorganic chemistry , benzyl alcohol , organic chemistry , ion , hydrogen , medicine , catalysis , endocrinology , methoxide
Lithium aluminum hydride (LAH), as well as other aluminum and boron hydrides lose their activity due to interaction with moist, oxygen and CO 2 even under good storing conditions. Discarding of such deteriorated reagents is neither economical or safe nor environmentally sound. Therefore, a convenient and fast assay for determining the quantity of reactive hydrides is desired. Such an assay for LAH, both as powder and in solution, is described. The method is based on the consumption of the reagent by excess methyl benzoate and calculation of its quantity from the ratio of the produced benzyl alcohol to the unreacted ester, as deduced from the integrated 1 H NMR spectrum of the reaction mixture. The procedure is easily performed and particularly adapted for the organic chemistry laboratory environment.