The Total Synthesis of the Galbulimima Alkaloid GB 13
Lewis N, Mander and Mathhew M. McLachlant
Link to PDF
So this might not be one of the newest papers, coming from back in the day (2002) but the post on Himadrine brought me to an older paper from Movassaghi (Galbulimia Alkaloid), bringing me to an earlier synth of it.
Lots of good chemistry in this paper, a Regitz Diazo Transfer, Wolff rearrangement, Birch reduction, an Eschenmoser fragmentation, and near the end of the paper, a nice cyclization.
So an early step of theirs was the Diazo Transfer where they attacked ethyl formate and then introduced the sulfonyl azide which then was attacked and then eliminated off the formaldehyde giving the Diazo Product. Here is a good paper testing out different reactions and conditions.
Once they had the Diazo they were able to do a Wolff rearrangment. Here they used light and a silyl group to catalyze the reaction. After an acidic workup they obtained a 68% yield which isnt too bad for rearrangement chem.
In the Birch Reduction they not only brought the anisole group down to the enone but also completel
y pull off cyanide and keep the stereochemistry while doing so. When they initally brought in the Lithium it removed the cyano group via reduction. Then the addition of methanol and acid pushed the Birch to reducing the Anisole.
Here is the fun step where they developed the ketone and terminal alkyne. Well in the Eschenmoser fragmentation they brought in the sulfonylhydrazine in ethanol and THF which, after alot of arrow pushing, will give you the desred alkynl ketone.
Finnaly one of the last steps they bring two oximes together with a plethera of reagents. The first being the ZrCl4 and NaBH4 which looks to me like the aldoxime is converted to the amine and then nuc's the other imine. Once the ketoxime is removed they remove the hydroxy group and then protect with TFAA. Heres a link to the oxime to amine paper they cited.
(Update! Just realized this step created 2 stereocenters with 100% ee. Since they didn't use any kind of chiral molecules to help induce the choice of cis, I'm guessing it is forced into this conformation by steric repulsion the previously created stereocenters.)
Alot of Chemistry in this paper. Very glad I stumbled upon it.
Lewis N, Mander and Mathhew M. McLachlant
Link to PDF
So this might not be one of the newest papers, coming from back in the day (2002) but the post on Himadrine brought me to an older paper from Movassaghi (Galbulimia Alkaloid), bringing me to an earlier synth of it.
Lots of good chemistry in this paper, a Regitz Diazo Transfer, Wolff rearrangement, Birch reduction, an Eschenmoser fragmentation, and near the end of the paper, a nice cyclization.
So an early step of theirs was the Diazo Transfer where they attacked ethyl formate and then introduced the sulfonyl azide which then was attacked and then eliminated off the formaldehyde giving the Diazo Product. Here is a good paper testing out different reactions and conditions.Once they had the Diazo they were able to do a Wolff rearrangment. Here they used light and a silyl group to catalyze the reaction. After an acidic workup they obtained a 68% yield which isnt too bad for rearrangement chem.
In the Birch Reduction they not only brought the anisole group down to the enone but also completel
y pull off cyanide and keep the stereochemistry while doing so. When they initally brought in the Lithium it removed the cyano group via reduction. Then the addition of methanol and acid pushed the Birch to reducing the Anisole. 
Here is the fun step where they developed the ketone and terminal alkyne. Well in the Eschenmoser fragmentation they brought in the sulfonylhydrazine in ethanol and THF which, after alot of arrow pushing, will give you the desred alkynl ketone.
Finnaly one of the last steps they bring two oximes together with a plethera of reagents. The first being the ZrCl4 and NaBH4 which looks to me like the aldoxime is converted to the amine and then nuc's the other imine. Once the ketoxime is removed they remove the hydroxy group and then protect with TFAA. Heres a link to the oxime to amine paper they cited.(Update! Just realized this step created 2 stereocenters with 100% ee. Since they didn't use any kind of chiral molecules to help induce the choice of cis, I'm guessing it is forced into this conformation by steric repulsion the previously created stereocenters.)
Alot of Chemistry in this paper. Very glad I stumbled upon it.
Very nice, sir.
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