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Chemistry and Biochemistry Publications

Series

Alkynes

Articles 1 - 5 of 5

Full-Text Articles in Chemistry

Nicholas Reactions Of Alkynyl- And Alkenyltrifluoroborates, Brent St. Onge, James R. Green Aug 2017

Nicholas Reactions Of Alkynyl- And Alkenyltrifluoroborates, Brent St. Onge, James R. Green

Chemistry and Biochemistry Publications

The Lewis acid mediated Nicholas reaction of potassium alkynyltrifluoroborates and propargyl acetate- hexacarbonyldicobalt complexes affords 1,4-diyne dicobalt hexacarbonyl complexes in good yields. The analogous Nicholas reactions of potassium alkenyltrifluoroborates give 1,3-enyne dicobalt hexacarbonyl complexes in most cases, although the initial site of reaction can vary. Potassium vinyltrifluoroborate itself affords alkynylcyclopropane complexes.


Synthesis Of Tenuifolin Via Intramolecular Nicholas Reaction, Sinisa Djurdjevic, James R. Green Oct 2014

Synthesis Of Tenuifolin Via Intramolecular Nicholas Reaction, Sinisa Djurdjevic, James R. Green

Chemistry and Biochemistry Publications

The synthesis of the Cinnamomum homosesquiterpenoid tenuifolin has been accomplished by way of an intramolecular Nicholas reaction of the [Co2(CO)6] complex of an alkyne-substituted biaryl for construction of the seven-membered ring. The cyclization features the reaction of a nonactivated arene ring with the propargyldicobalt cation to give the dibenzocycloheptyne-Co2(CO)6.


Synthesis Of ‘Spacer’-Naproxen [2-(6-Methoxybiphenylen-2-Yl)Propanoic Acid] And -Isonaproxen [2-(7-Methoxybiphenylen-2-Yl)Propanoic Acid], Juan A. González Gómez, James R. Green, Peter C. Vollhardt Apr 2011

Synthesis Of ‘Spacer’-Naproxen [2-(6-Methoxybiphenylen-2-Yl)Propanoic Acid] And -Isonaproxen [2-(7-Methoxybiphenylen-2-Yl)Propanoic Acid], Juan A. González Gómez, James R. Green, Peter C. Vollhardt

Chemistry and Biochemistry Publications

The CpCo(CO)2-catalyzed cocyclization of 1,2-diethynyl- 4-methoxybenzene with alkynes can be applied to the synthesis of ‘spacer’-naproxen [2-(6-methoxybiphenylen-2-yl)propanoic acid] and its 7-methoxy isomer, ‘spacer’-isonaproxen. While unsymmetrical alkynes are incorporated without regioselectivity, the methoxy group in 6-methoxy-2,3-bis(trimethylsilyl)biphenylene directs electrophiles to C-3, thus allowing for regiochemical differentiation between the 2- and 3-positions.


Benzocycloheptynedicobalt Complexes By Intramolecular Nicholas Reactions, Y. Ding, James R. Green Jan 2005

Benzocycloheptynedicobalt Complexes By Intramolecular Nicholas Reactions, Y. Ding, James R. Green

Chemistry and Biochemistry Publications

Lewis acid mediated intramolecular Nicholas reactions of aryl (Z)-enyne propargyl acetate-CO2(CO)(6) complexes 1 afford benzocycloheptenyne-CO2(CO)(6) complexes 2 and their heterocyclic analogues.


Intramolecular Pauson-Khand Reactions Of Cycloheptynedicobalt Complexes, Ahmed B. Mohamed, James R. Green, Jason Masuda Jan 2005

Intramolecular Pauson-Khand Reactions Of Cycloheptynedicobalt Complexes, Ahmed B. Mohamed, James R. Green, Jason Masuda

Chemistry and Biochemistry Publications

Cycloheptyne-Co-2(CO)(6) complexes bearing alkenes tethered by oxygen, sulfur, and nitrogen atoms undergo Pauson-Khand reactions to afford tricyclic compounds containing a fused 7,5-ring system.