dragonfly - 21-9-2006 at 09:51
Hi all
Does anyone have a suggestion on how to go about preparing formyl isocyanate.
As yet ?I have been unable to find any refrences to a procedure. I imagine one would begin with formamide. What then? carbon dioxide, pressure and a
catalyst such as raney nickle?
[Edited on 21-9-2006 by dragonfly]
Nicodem - 21-9-2006 at 11:26
Are you sure it exists?
I can only find references to theoretical studies, DFT and spectroscopy calculations but nothing on that species as a compound. Perhaps it does not
exist as a stable compound (like formyl chloride, for example).
PS: From formamide it could utmost form by the reaction with phosgene (or triphosgene) in pyridine, but certainly not with CO2.
solo - 21-9-2006 at 11:53
Experimental Investigation of the Reaction between Nitric Oxide and Ketenyl Radicals (HCCO + NO): Rate Coefficient at T = 290-670 K and
Product Distribution at 700 K
Werner Boullart, Minb Tho Nguyen, and Jozef Peefed
J. Phys. Chem. 1994,98, 8036-8043
Abstract
The HCCO + NO reaction (r5) was investigated in C2H2/0/NO systems at a pressure of 2 Torr (He bath gas) using discharge flow-molecular beam mass
spectrometry techniques (DF-MBMS). The first rate coefficient
data at temperatures > 300 K are presented. The coefficient was measured relative to the known k(HCCO+O) from the changeof steady-state HCCO
signals upon adding increasing amounts of NO. Thus, in the temperature
range from 290 to 670 K, the k(HCCO+NO) coefficient was found to exhibit a slight but significant temperature dependence: k(T) = (1.0 f 0.3) X 10-lo
e-(350*150)/(TIcQm 3 molecule-’ (T = 290-670 K). The product
distribution was determined at 700 K. The experiments relied on the fact that all reaction pathways yield either CO or C02. Ketenyl radicals,
generated by quantitative reaction of a known amount of 0 atoms with C2H2
in high excess, were reacted with a large excess of NO, ensuring quantitative conversion into the products C02 and CO. The product distribution was
essentially deduced from the ratios [CO2]fomd/[O]input and [CO]for,d/
[O]inPut. Formation of CO together with CHz(3B1) in a minor (25 f 15%) channel of the C2H2 + 0 reaction was taken into account. Small corrections for
secondary reactions such as HCCO + 0 - H + 2 CO were made
by kinetic modeling.
Thus, the following yields were obtained: for HCCO + NO - (CHNO) + CO, 77 f
9%; for HCCO + NO - (CHN) + C02, 23 f 9%. Strong product signals were also observed at m/e = 43 and m/e = 27, confirming that CHNO isomers and CHN
isomers are formed along with CO and COz, respectively. Theoretical predictions regarding the CO/CO2 yield ratio, presented in a companion paper in
this issue, can be reconciled with the experimental product distribution only when an as yet unidentified entrance pathway to the formyl isocyanate
intermediate is assumed to exist and to be thermally accessible.
Attachment: Experimental Investigation of the Reaction between Nitric Oxide and Ketenyl Radicals .pdf (917kB)
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dragonfly - 26-9-2006 at 03:33
Hi Nicodem and Solo
Thank you for your responses. This is clearly an impractical approach to a new project
The idea behind this question originates from a request I recieved. I was asked to prepare a methylenemethanamine type polymer. I fiqured the formyl
isocyanate would be the best place to start. Any ideas ?
I thought that if I was to react the formylisocyanate with methyldiamine the polymer would at the very least be interesting- Expect to have
electrical, optical and perhaps some elastomer type properties.
What are your thoughts?