C O M M U N I C A T I O N S
Scheme 3
In summary, we found a new method of introducing alkynyl
groups to the â-position of R,â-unsaturated ketones with high
enantioselectivity, which was realized by rhodium-catalyzed asym-
metric 1,3-migration of alkynyl groups from 1 position to 3 in
alkynyl alkenyl carbinols. The catalytic cycle presumably involves
the â-alkynyl elimination from an alkoxyrhodium intermediate as
a key step.
Table 1. Asymmetric Rearrangement of Alkynyl Alkenyl
Carbinolsa
Acknowledgment. This work was supported by a Grant-in-Aid
for Scientific Research on Priority Areas “Advanced Molecular
Transformations of Carbon Resources” from the Ministry of
Education, Culture, Sports, Science and Technology, Japan.
Supporting Information Available: Experimental procedures and
spectroscopic and analytical data for the substrates and products (pdf).
This material is available free of charge via the Internet at http://
pubs.acs.org.
References
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a Reaction conditions: alcohol 3 (0.20 mmol), [Rh(OH)(cod)]2 (5 mol
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