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The Heck reaction is one of the most reliable and useful strategies for the construction of C–C bonds in organic synthesis. However, in contrast to the well-established aryl Heck reaction, the analogous reaction employing alkyl electrophiles is much less developed. Significant progress in this area was recently achieved by merging radical-mediated and transition-metal-catalyzed approaches. This review summarizes the advances in alkyl Heck-type reactions from its discovery early in the 1970s up until the end of 2018. 1 Introduction 2 Pd-Catalyzed Heck-Type Reactions 2.1 Benzylic Electrophiles 2.2 α-Carbonyl Alkyl Halides 2.3 Fluoroalkyl Halides 2.4 α-Functionalized Alkyl Halides 2.5 Unactivated Alkyl Electrophiles 3 Ni-Catalyzed Heck-Type Reactions 3.1 Benzylic Electrophiles 3.2 α-Carbonyl Alkyl Halides 3.3 Unactivated Alkyl Halides 4 Co-Catalyzed Heck-Type Reactions 5 Cu-Catalyzed Heck-Type Reactions 6 Other Metals in Heck-Type Reactions 7 Conclusion
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Synergistic palladium/enamine catalysis for asymmetric hydrocarbon functionalization of unactivated alkenes with ketones
Synergistic palladium and enamine catalysis was explored to promote ketone addition to unactivated olefins. A secondary amine-based organocatalyst was identified as the optimal co-catalyst for the directed Pd-catalyzed alkene activation. Furthermore, asymmetric hydrocarbon functionalization of unactivated alkenes was also achieved with good to excellent yield (up to 96% yields) and stereoselectivity (up to 96% ee). This strategy presented an efficient approach to prepare α-branched ketone derivatives under mild conditions.
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- Award ID(s):
- 1665122
- PAR ID:
- 10181399
- Date Published:
- Journal Name:
- Organic & Biomolecular Chemistry
- Volume:
- 17
- Issue:
- 27
- ISSN:
- 1477-0520
- Page Range / eLocation ID:
- 6607 to 6611
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9ob01165j
