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ABSTRACT: Studies have described a highly convergent plan toward the synthesis of leiodolide A (1), a potent cytotoxic sponge metabolite. The enantiocontrolled preparation of aldehyde 6 is achieved with the application of several advances of methodology for the synthesis of substituted 1,3-oxazoles. Efforts have examined the halogen dance reaction, the selectivity of Stille cross coupling reactions of 4-bromo-1,3-oxazoles, and nucleophilic displacement of the 2-phenylsulfonyl substitu-ent with organolithium reagents as preparatively useful reactions. These techniques have facilitated the efficient synthesis of 6 from the starting bromide 12, alkenylstannane 16 and the primary nonracemic alcohol 25.
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This content will become publicly available on January 1, 2026
Improved Synthesis of Lithium Dendrites for the Synthesis of Trimethylsilylmethyllithium
In the preparation of organolithium reagents, the use of highly activated lithium metal surfaces is essential. Currently, commercially available sources provide high surface area lithium in the form of powders or dispersions. Our group has presented a new approach to synthesize lithium with clean and high surface areas up to 100 times greater than conventional Li-dispersion. Our method involves the use of liquid ammonia (NH3) to effectively clean the lithium surface, resulting in the controlled dendritic growth of lithium structures along the flask wall. This freshly synthesized and highly activated lithium exhibits consistency and reliability, enabling the scalable production of organolithium reagents, ranging from 0.1 mmol to 0.5 mole. Herein, we outline the procedure for applying 5 grams of Li-dendrites in the synthesis of (trimethylsilyl)methylchloride, highlighting the potential impact of our method on organometallic chemistry.
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- Award ID(s):
- 2238881
- PAR ID:
- 10590945
- Publisher / Repository:
- Organic Syntheses
- Date Published:
- Journal Name:
- Organic Syntheses
- ISSN:
- 2333-3553
- Page Range / eLocation ID:
- 1 to 18
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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