From: Starcrown (stch8002$##$bureau.ucc.ie)
Date: Tue Jul 06 1999 - 15:23:25 EDT
>> I know this is a basic query but any suggestions are appreciated. In
>> our lab, we seem to have difficulty in obtaining dry THF on a consistent
>> basis. In the past, we have distilled it from KOH, and then from
>> Na/benzophenone ketyl. [SNIP]
My own experience over ca. 20 yrs of drying THF has been that just Na (as
thin WIRE) and benzophenone works .... most of the time. However now and
then we encounter THF (from the same supplier as normal) which is
troublesome. Either the blue ketyl appears to deteriorate faster than usual
or - more frustratingly - never appears at all even after extensive reflux.
In those cases pre-treatment of the THF in a variety of ways did not remove
the problem. We have never found an explanation for this behaviour - but at
least our experience may indicate that the solvent itself, rather than your
drying method, may be the source of the difficulty.
Regards -
Fergus Lalor
--------------------------------------------------
Dr. Fergus Lalor, Chemistry Dept., University
College, Cork, IRELAND.
Telephone: 353-(0)21-902317. Fax: 353-(0)21-274097
E-mail: STCH8002$##$BUREAU.UCC.IE
dein goldenes Haar Margarete
dein aschenes Haar Shulamith
'Todesfuge', Paul Celan (1920-1970).
but also ....
Mairidh Gaol is Ceol
and ...
'I hear the ancient footsteps like the motion of the sea
Sometimes I turn, there's someone there - other times it's only me ...'
(Bob Dylan - 'Every Grain of Sand')
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