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Please login to access the full content or check if you have access via2.10.1 Enantioselective Addition of Acetylide Nucleophiles to Carbonyl Compounds
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Carreira, E. M.; Frantz, D. E., Science of Synthesis: Stereoselective Synthesis, (2011) 2, 497.
General Introduction
Chiral propargylic alcohols can be found as structural motifs in several natural products and pharmaceuticals. However, their most important attribute is their use as versatile chiral building blocks in organic synthesis.[1] This has only recently become true due to the dramatic development of new methodologies within the past decade that have provided access to these substrates with unprecedented enantioselectivities. Undoubtedly, most modern asymmetric approaches to chiral propargylic alcohols involve the addition of metal acetylides to carbonyl compounds mediated through the use of chiral external ligands. The advantage of this approach over classical asymmetric reductions of alkynyl ketones is the simultaneous formation of a carbon—carbon bond and stereogenic center in a single step (Scheme 1). This area has been recently reviewed and a comprehensive summary of the various approaches toward enantioselective addition of alkyne nucleophiles to both aldehydes and ketones can be found within these references.[1–7] Thus, what will be presented here is a selection of the most successful reactions with respect to yield and enantioselectivity while keeping practicality, costs, and the availability of starting materials as equally important considerations.
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References
[1] | Meeee, M. M.; Meeee, M. M., Mee. Meeee. Meeee., (8888) 888, 888. |
[2] | Meeeeee, M., Meee. Mee. Meee., (8888) 88, 8888. |
[3] | Mee, M.; Mee, M., Meee. Mee. Meee., (8888) 88, 8888. |
[4] | Mee, M.; Meee, M., Meee. Mee. Meee., (8888) 88, 8888. |
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[6] | Me, M.; Me, M.-M.; Me, M.-M.; Meee, M. M. M., Meeee. Meee. Mee., (8888) 888, 8888. |
[7] | Me, M., Meeeeeeeeee, (8888), 88, 8888. |