Sciencemadness Discussion Board

2-methyltetrahydrofuran interchangeability

CycloRook - 29-1-2022 at 13:13

Can these 2 solvents be used in a grignard interchangeably Tetrahydrofuran?

Thanks

[Edited on 29-1-2022 by cycloknight19]

Mush - 29-1-2022 at 16:01

Solvent Applications of 2-Methyltetrahydrofuran in Organometallic and Biphasic Reactions

2-Methyltetrahydrofuran (MeTHF) is a commercially available solvent that is produced from renewable resources. The properties of MeTHF place it between tetrahydrofuran (THF) and diethyl ether in solvent polarity and Lewis base strength. In many cases, MeTHF can replace THF in organometallic reactions. The formation and reaction of Grignard reagents in MeTHF and THF are similar. MeTHF can be used as a solvent for low-temperature lithiation, for lithium aluminum hydride reductions, for the Reformatsky reaction, and for metal-catalyzed coupling reactions. MeTHF is also a good substitute for dichloromethane in biphasic reactions.

Org. Process Res. Dev. 2007, 11, 1, 156–159
doi.org/10.1021/op060155c

Grignard Reagents in 2-MeTHF

Recent advancements on the use of 2-methyltetrahydrofuran in organometallic chemistry

Abstract

Since the introduction of 2-methyltetrahydrofuran as an useful alternative to the classical tetrahydrofuran, there has been a continuous interest in the synthetic community operating at academic and industrial towards it. In particular, the much higher stability that basic organometallic reagents display in 2-methyltetrahydrofuran makes it suitable for processes involving such sensitive species including asymmetric transformations. The easy formation of an azeotropic mixture with water, the substantial immiscibility with water, and the fact it derives from natural sources (corncobs or bagasse), allow to consider it in agreement with the Anastas’ Geen Chemistry principles. In this minireview, selected examples of its employment in organometallic transformations ranging from carbanions to radical and transition metal-catalyzed processes are provided.

Monatshefte für Chemie - Chemical Monthly volume 148, pages 37–48 (2017)

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CycloRook - 30-1-2022 at 09:32

I see thank you.

It looks like this is actually a better solvent since it's easier to keep anhydrous.

Dr.Bob - 30-1-2022 at 09:45

it has a higher flash point, which is why process chemists like it, and boils higher, so easier to do higher temp reactions in it. It is nearly interchangable with THF, and more stable to strong base and reductants, I believe, due to the sterics from the methyl group. I just used some recently, and it worked great instead of THF for a scaleup.