77611-71-3Relevant articles and documents
London Dispersion in Alkane Solvents
Strauss, Marcel A.,Wegner, Hermann A.
supporting information, p. 779 - 786 (2020/11/30)
The importance of London dispersion interactions in solution is an ongoing debate. Although the significance of dispersion for structure and stability is widely accepted, the degree of its attenuation in solution is still not properly understood. Quantita
Exploring London Dispersion and Solvent Interactions at Alkyl–Alkyl Interfaces Using Azobenzene Switches
Strauss, Marcel A.,Wegner, Hermann A.
supporting information, p. 18552 - 18556 (2019/11/19)
Interactions on the molecular level control structure as well as function. Especially interfaces between innocent alkyl groups are hardly studied although they are of great importance in larger systems. Herein, London dispersion in conjunction with solvent interactions between linear alkyl chains was examined with an azobenzene-based experimental setup. Alkyl chains in all meta positions of the azobenzene core were systematically elongated, and the change in rate for the thermally induced Z→E isomerization in n-decane was determined. The stability of the Z-isomer increased with longer chains and reached a maximum for n-butyl groups. Further elongation led to faster isomerization. The origin of the intramolecular interactions was elaborated by various techniques, including 1H NOESY NMR spectroscopy. The results indicate that there are additional long-range interactions between n-alkyl chains with the opposite phenyl core in the Z-state. These interactions are most likely dominated by attractive London dispersion. This work provides rare insight into the stabilizing contributions of highly flexible groups in an intra- as well as an intermolecular setting.
Palladium-Catalyzed Methylation of Nitroarenes with Methanol
Wang, Lin,Neumann, Helfried,Beller, Matthias
supporting information, p. 5417 - 5421 (2019/04/04)
A procedure for the synthesis of N-methyl-arylamines directly from nitroarenes using methanol as green methylating agent was developed. The key to success is the use of a specific catalyst system consisting of palladium acetate and the ligand 1-[2,6-bis(isopropyl)phenyl]-2-[tert-butyl(2-pyridinyl)phosphino]-1H-Imidazole (L1). The generality of this protocol is demonstrated in the synthesis of more than 20 N-methyl-arylamines under comparably mild conditions. Combining this novel methodology with subsequent coupling processes using the same catalyst allows for efficient diversification of aromatic nitro compounds to a broad variety of amines including drug molecules.
