C O M M U N I C A T I O N S
lectivity.12 This complexity generating reaction sets four contiguous
stereocenters and allows access to novel functionalized chroman
derivatives, an important pharmacophore.13
Table 2. Evaluation of Scope
In conclusion, we have developed a highly enantioselective Pd-
catalyzed alkene difunctionalization reaction involving the addition
of two distinct nucleophiles, a process which allows for the
formation of complex chiral molecules from relatively simple
starting materials. Future work will focus on expansion of the scope
to include other types of nucleophiles and Diels-Alder partners,
improvement of reaction conditions to reduce the required amount
of the second nucleophile, and development of a deeper understand-
ing of the mechanistic details of the reaction.
Acknowledgment. This work was supported by the National
Institutes of Health (NIGMS RO1 GM3540). Crystal structure
analysis was performed by Atta Arif. We thank Gary Keck and
Ryan Looper for insightful discussions.
Supporting Information Available: Experimental procedures and
full spectroscopic data for new compounds. This material is available
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JA909030C
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