Dimesityldioxirane
{{Short description|Chemical compound}}
{{chembox
| Name = Dimesityldioxirane
| ImageFile = Dimesityldioxirane.png
| IUPACName = 3,3-bis(2,4,6-trimethylphenyl)dioxirane
| Section1 = {{Chembox Identifiers
| CASNo = 161807-01-8
| CASNo_Ref = {{Cascite|changed|CAS}}
| ChemSpiderID = 74833282
| InChI = 1S/C19H22O2/c1-11-7-13(3)17(14(4)8-11)19(20-21-19)18-15(5)9-12(2)10-16(18)6/h7-10H,1-6H3
| InChIKey = CIQXXABRSWBHGW-UHFFFAOYSA-N
| PubChem = 86180054
| SMILES = CC1=CC(=C(C(=C1)C)C2(OO2)C3=C(C=C(C=C3C)C)C)C
}}
| Section2 = {{Chembox Properties
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| Formula = C19H22O2
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| MolarMass = 282.4 g/mol
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Dimesityldioxirane is a substituted dioxirane with two mesityl groups attached to the dioxirane carbon. It is a colorless crystalline substance stable in its solid state around -20 °C.{{Cite journal |last=Kirschfeld |first=Andreas |last2=Muthusamy |first2=Sengodagounder |last3=Sander |first3=Wolfram |date=1994-11-17 |title=Dimesityldioxirane—A Dioxirane Stable in the Solid State |url=https://onlinelibrary.wiley.com/doi/10.1002/anie.199422121 |journal=Angewandte Chemie International Edition in English |language=en |volume=33 |issue=21 |pages=2212–2214 |doi=10.1002/anie.199422121 |issn=0570-0833}}
Structure
The molecule possesses approximately C2 symmetry and the mesityl groups are twisted by 54.2°. The bulky mesityl groups cause steric strain which is reduced by increase in R1–C–R2 angle from 117° in dioxirane to 119.2° in dimesityldioxirane. The mesityl groups also rotate about the single bond, consequently reducing steric repulsions further.{{cite journal |last=Sander |first=Wolfram |last2=Schroeder |first2=Kerstin |last3=Muthusamy |first3=Sengodagounder |last4=Kirschfeld |first4=Andreas |last5=Kappert |first5=Wilhelm |last6=Boese |first6=Roland |last7=Kraka |first7=Elfi |last8=Sosa |first8=Carlos |last9=Cremer |first9=Dieter |date=1997-08-01 |title=Dimesityldioxirane |journal=Journal of the American Chemical Society |volume=119 |issue=31 |pages=7265–7270 |doi=10.1021/ja964280n |issn=0002-7863}}
Synthesis and Uses
Dimesityldioxirane was first isolated at room temperature in pure as well as in solution form in 1994.{{Cite thesis |title=Epoxidation using dioxiranes |url=https://repository.lboro.ac.uk/articles/thesis/Epoxidation_using_dioxiranes/9397010/1 |publisher=Loughborough University |date=1996-01-01 |degree=PhD |language=en |first=Lesley |last=Walton}} It was synthesised by irradiation of its diazo derivative in trichlorofluoromethane at 183K to form {{chem name|dimesitylcarbene}}, followed by oxidation. The synthesis had a yield of 50%.
It can mainly be used as an oxidizing agent but is less oxidizing than other dioxiranes due to its stability.