64822-81-7Relevant academic research and scientific papers
Unified synthesis of C1-C19 building blocks of halichondrins via selective activation/coupling of polyhalogenated nucleophiles in (Ni)/Cr-Mediated reactions
Li, Jingwei,Yan, Wuming,Kishi, Yoshito
, p. 6226 - 6231 (2015)
A unified synthesis of the C1-C19 building blocks 8-10 of halichondrins A-C was developed from the common synthetic intermediates 26a,b. Acetylenic ketones 26a,b were in turn synthesized via selective activation/coupling of polyhalogenated nucleophiles 23
Regioselectivity in the formation of small- and medium-sized cyclic ethers by diene-ene ring-closing metathesis
Basu, Sudipta,Waldmann, Herbert
, p. 3977 - 3979 (2006)
In the formation of medium-sized ethers by diene-ene ring-closing metathesis, the formation of cyclic allyl ethers with a smaller ring size and of pentadienyl ethers with a larger ring size compete with each other. In the competition between six- and eight-membered and seven- and nine-membered ring formation, the smaller rings are formed exclusively, whereas in the competition between the five- and seven-membered rings, both products are formed in comparable amounts.
CHROMIUM-MEDIATED COUPLING AND APPLICATION TO THE SYNTHESIS OF HALICHONDRINS
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Paragraph 00453; 00455, (2016/11/17)
The present invention provides unified synthesis of the CI -CI 9 building blocks of halichondrins and analogs theoreof using selective coupling of poly-halogenated nucleophiles in chromium-mediated coupling reactions. The present invention also provides a practical and efficient synthesis of C20-C38 building blocks of halichondrins and analogs thereof. Also provided herein are general methods of selective activation and coupling of poly-halogenated analogs with an aldehyde. The provided coupling reactions are selective for halo-enone and halo-acetylenic ketal over vinyl halide and halide attached to a sp hydridized carbon. The provided efficient selective coupling reactions can allow easy access to the CI -CI 9 building blocks and C20-C38 building blocks of halichondrins and analogs thereof with limited or no purification or separation of the intermediates.
