The Vespiary

The Hive => Chemistry Discourse => Topic started by: silenziox on October 27, 2003, 01:43:00 AM

Title: GBL via THF (exotic ruthenium reagent)
Post by: silenziox on October 27, 2003, 01:43:00 AM
What the hell is "trans-2" and where to get it?


Reaction 18 (exotic ruthenium reagent)
trans-<Ru%VI&(N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)propylenediamine)O2><ClO4>2
Solvent: acetonitrile
Time: 1 hour
Temperature: 25 C
Yield 98%
Ref. 1 5541107; Journal; Che, Chi-Ming; Tang, Wai-Tong; Li, Chi-Keung; JCDTBI; J.Chem.Soc.Dalton Trans.; EN; 12; 1990; 3735-3739;





Title: Exotic ruthenium agent
Post by: Chromic on October 27, 2003, 04:03:00 AM
I think it's ruthenium(IV) oxide with a substituted propylenediamine ligand chelated to it. (this is a polydentate ligand, coordinating with its 4 nitrogens)

I wonder what that 2 part is about, it seems to indicate two perchlorate groups, but I have no idea how that would fit in.. perhaps its a bridging ligand (but how would the charge balance?)

I'm just guessing here, but I think one would have to prepare this compound--not purchase it. Unless you've got access to Sigma/Fischer/Aldrich, and a fair amount of money to spend on ruthenium salts (they're not terribly expensive--but not terribly cheap either)... don't even bother thinking twice about this reagent... and if you did have such access, you'd just buy a drum or twelve of GBL anyhow.
Title: Valence note
Post by: Rhodium on October 27, 2003, 09:39:00 PM
The name actually says Ru6+ (and not Ru4+), so all the ligands would actually "fit".
Title: Dylexic
Post by: Chromic on October 28, 2003, 12:01:00 AM
RuO2(ClO4)2 with the substituted diamine coordinated to it makes sense if the ruthenium is 6+... Rhodium is absolutely right. Sorry about my dyslexia.  :)
Title: Oxidation of THF to GBL in 98% yield with Ru(VI)
Post by: Rhodium on September 21, 2004, 09:45:00 PM
Full text to the above-mentioned article:

Synthesis, Electrochemistry, and Reactivities of trans-[Ru(L)O2]2+ (L = N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)propylenediamine
Chi-Ming Che, Wai-Tong Tang, and Chi-Keung Li

J. Chem. Soc. Dalton Trans 3735-3739 (1990) (https://www.thevespiary.org/rhodium/Rhodium/pdf/thf2gbl.ruo2l2.pdf)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/thf2gbl.ruo2l2.pdf)

Abstract
The synthesis and characterization of the ligand N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)propylenediamine (L) and the complex trans-[Ru(L)O2]2+ are described. The complex has been characterized by uv-visible [dxy ? d?* (d?* = dxz,dyz) at 380-420 nm] and IR [Vasym(RuO2) at 860 cm-1] spectroscopy. At pH 1.0 it exhibits three reversible couples RuVI-RuIV RuIV-RuIII, and RuIII-RuII at potentials of 0.89, 0.60, and 0.28 V respectively vs. saturated calomel electrode. The RuVI-RuIV couple splits into two reversible one-electron couples RuVI-RuV and RuV-RuIV in alkaline solutions (pH > 9). The complex is a powerful oxidant, capable of oxidizing toluene to benzaldehyde, alcohols to aldehydes/ketones, tetrahydrofuran to ?-butyrolactone, and norbornene to exo-2,3-epoxy-norbornane in high yields at room temperature. Oxidation of cis- and trans-stilbenes gave benzaldehyde and trans-stilbene oxides.