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Abstract We report herein a Cu‐catalyzed regio‐, diastereo‐ and enantioselective acylboration of 1,3‐butadienylboronate with acyl fluorides. Under the developed conditions, the reactions provide (Z)‐β,γ‐unsaturated ketones bearing an α‐tertiary stereocenter with highZ‐selectivity and excellent enantioselectivities. While direct access to highly enantioenrichedE‐isomers was not successful, we showed that such molecules can be synthesized with excellentE‐selectivity and optical purities via Pd‐catalyzed alkene isomerization from the correspondingZ‐isomers. The orthogonal chemical reactivities of the functional groups embedded in the ketone products allow for diverse chemoselective transformations, which provides a valuable platform for further derivatization.
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A Conformer‐Dependent, Quantitative Quadrant Model
Abstract This study reports the development and application of a conformer‐dependent quantitative quadrant descriptor for generating models that relate catalyst performance to catalyst structure in enantioselective transformations. The generality of these descriptors is demonstrated by using them for three different reactions: (1) copper‐catalyzed, enantioselective cyclopropanation of alkenes, (2) rhodium‐catalyzed enantioselective hydrogenation ofα‐substitutedN‐acyl‐enamides, and (3) enantioselective addition of thiols toN‐acyl imines. This work will provide researchers an interpretable steric descriptor that merges the heuristic value of quadrant models with a quantitative tool that can be used to create statistically meaningful correlations between the steric occupancy of catalyst quadrants and stereoselectivity. The low dimensionality of this descriptor, its ability to capture conformational effects and stereostructure, and its direct relationship to intuitive structural properties make it particularly well‐suited for creating Quantitative Structure‐Selectivity Relationships (QSSR) with smaller datasets of asymmetric reactions.
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- Award ID(s):
- 1900617
- PAR ID:
- 10251812
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- European Journal of Organic Chemistry
- Volume:
- 2021
- Issue:
- 17
- ISSN:
- 1434-193X
- Format(s):
- Medium: X Size: p. 2343-2354
- Size(s):
- p. 2343-2354
- Sponsoring Org:
- National Science Foundation
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