Synthetic Route of 33100-27-5. Chemistry is an experimental science, and the best way to enjoy it and learn about it is performing experiments.Introducing a new discovery about 33100-27-5, Name is 1,4,7,10,13-Pentaoxacyclopentadecane
A series of six-coordinate chloro CrIII and VIII complexes involving crown ether, crown thioether and mixed ether/thioether crowns, [MCl3(crown)] (M = Cr or V; crown = 12-crown-4, 15-crown-5,18-crown-6, [12]aneS4, [15]aneS5, [9]aneS 2O, [15]aneS2O3, [18]aneS3O 3) has been prepared by the reaction of [MCl3(thf) 3] with rigorously dried crown in anhydrous CH2Cl 2. In the presence of small amounts of water the monoaquo species [MCl3(H2O)(15-crown-5)] and [MCl3(H 2O)(18-crown-6)] are obtained. The products have been characterised by IR and UV/Visible spectroscopy, microanalyses and for [CrCl 3(H2O)(18-crown-6)], [VCl3(H 2O)(15-crown-5)] and [CrCl3([15]aneS5)], by X-ray crystallography. The unexpected affinity of specifically the 15-crown-5 and 18-crown-6 complexes to pick up H2O is rationalised in terms of the strain within the two adjacent five-membered chelate rings in the anhydrous (kappa3-coordinated) species, and a wider survey of the structures reported for six-coordinate MIII crown complexes (M = Sc – Cr) with RECH2CH2ER (E = O or S) reveals that while the S-M-S angles in five-membered chelate rings are typically around 82, those involving O-M-O are very substantially more acute at around 75. Thus, the [MCl3(kappa3-crown ether)] complexes are much less stable and can alleviate some of this significant ring strain by switching to kappa2-crown coordination with the H2O ligand completing the six coordination. In contrast, the crown thioether complexes have much less tendency to do this and hence appear to be more stable. Furthermore, using the structurally related (dimethylene linkages) mixed thia/oxa crowns to probe the M-O vs. M-S binding competitively, strongly indicates that the CrIII and VIII preferentially coordinate to the thioether rather than the ether donor atoms, contrary to normal expectation based upon HSAB theory. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
If you are hungry for even more, make sure to check my other article about 33100-27-5. Synthetic Route of 33100-27-5