Highly Efficient Synthesis of New a-Arylamino-a’-chloropropan-2-ones
FULL PAPERS
Scheme 11. Fast and mild cleavage of aryltrifluoroacetamides.
thanks the Ministerio de Ciencia e Innovaciꢀn for a Ph.D.
grant (Ref. FPU-AP-2005-5112).
Conclusions
To conclude, in this work we have shown for the first
time how the oxidative hydrolysis of different protect-
ed N-(2-chloroallyl)anilines promoted by calcium hy-
pochlorite is able to yield different a-arylamino-a’-
chloropropan-2-ones, not previously described, in ex-
cellent yields and short reaction times. The oxidative
agent calcium hypochlorite is more suitable for this
process compared to the usually employed sodium hy-
pochlorite. On the other hand, the main requirement
of the reaction for avoiding the undesired aromatic
chlorination (N-protection) is effectively solved by
the use of the trifluoroacetamide group, easy to intro-
duce and to remove, therefore leading to the desired
compounds in a very convenient methodology.
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Experimental Section
General Procedure for the Oxidative Hydrolysis of
Arylaminovinyl Chlorides
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To a solution (08C) of vinyl chloride (22–26, 1.00 mmol) in
acetone-acetic acid (5:2, 2.0 mL) cooled at 08C an aqueous
solution (1.50 mL) of calcium hypochlorite (1.50 mmol) was
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This work was partly supported by a Research Project of the
CAM (Comunidad Autꢀnoma de Madrid, QO-UCM) (Ref.
S-0505/PPQ/0344) and MEC (Ministerio de Educaciꢀn y
Ciencia) CTQ2006-09052. One of the authors (V. Pace)
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