Structurally complex diazo‐containing scaffolds are formed by conjugate addition to vinyl diazonium salts. The electrophile, a little studied α‐diazonium‐α,β‐unsaturated carbonyl compound, is formed at low temperature under mild conditions by treating β‐hydroxy‐α‐diazo carbonyls with Sc(OTf)3. Conjugate addition occurs selectively at the 3‐position of indole to give α‐diazo‐β‐indole carbonyls, and enoxy silanes react to give 2‐diazo‐1,4‐dicarbonyl products. These reactions result in the formation of tertiary and quaternary centers, and give products that would be otherwise difficult to form. Importantly, the diazo functional group is retained within the molecule for future manipulation. Treating an α‐diazo ester indole addition product with Rh2(OAc)4caused a rearrangement to occur to give a 2‐(1
This content will become publicly available on May 15, 2025
- Award ID(s):
- 2102229
- PAR ID:
- 10516623
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Organic & Biomolecular Chemistry
- Volume:
- 22
- Issue:
- 21
- ISSN:
- 1477-0520
- Page Range / eLocation ID:
- 4274 to 4277
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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