ansa-Ruthenium(II) Complexes of R2NSO2DPEN-(CH2)n(h6-Aryl) Conjugate Ligands
UPDATES
rise above 08C. After stirring for 30 min at such a tem-
perature and for 1 h at room temperature, a cold (08C)
Acknowledgements
solution
of
(S,S)-N-(1-piperidylsulfonyl)DPEN
This work was supported by the Ministry of Higher Educa-
tion, Science, and Technology of the Republic of Slovenia
(Grant No. P1-242).
(1.00 equiv.) in CH2Cl2 is added and stirred overnight
at room temperature. After a standard CH2Cl2-extrac-
tive work-up, 85–92% of pure 3 is obtained. See also
the Supporting Information.
[7] Although we failed to isolate any monomeric Ru(II)
structure 1, their formation as such is evidenced by the
resulting high catalyst activity and enantioselectivity. In
References
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for 100% conversion) and 96.3% ee (4 h for >99%
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[4] The structure B depicted in Figure 1 is suggested based
on the X-ray-characterized analogous complex A of
Wills et al.[2a]
[5] For a preparation of (S,S)-R2NSO2DPEN, see: D.
ˇ
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[6] The following improved adapted protocol uses less
amounts of reagents and obviates the need for Et3N re-
sulting in higher yields: To a cold (08C) solution of 2
(1.19 equiv.) and 2,6-lutidine (1.44 equiv.) in CH2Cl2 is
added a solution of triflic anhydride (1.22 equiv.) in
CH2Cl2 at a such a rate that the temperature does not
Adv. Synth. Catal. 2015, 357, 2540 – 2546
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