| 1. |
- Alvi, Muhammad Rouf, et al.
(författare)
-
Scope and Limitations of an Acid Catalyzed Protocol for Hypersilyl Protection of Alcohols
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- A highly efficient and convenient triflic acid (TfOH) catalyzed protocol for the protection of various functionalized alcohols in CH2Cl2 at ambient temperature using tris(trimethylsilyl)silyl-N,N-dimethyl-methaneamide (hypersilylamide) 1 as the protecting reagent is developed. Herein, results on the scope and limitations of this protocol for a number of functionalized alcohols are presented. This method was found to be effective for the selective protection of less hindered OH groups in different classes of diols containing both pri/tert, sec/tert, or aromatic/aliphatic hydroxyl groups. In general, our protocol exhibited excellent functional group tolerance in the protection of alcohols containing alkoxy, keto, amino, as well as halo substituents in good to excellent yields.
|
|
| 2. |
- Finke, Aaron D., et al.
(författare)
-
The 6,6-Dicyanopentafulvene Core : A Template for the Design of Electron-Acceptor Compounds
- 2015
-
Ingår i: Chemistry - A European Journal. - : Wiley. - 0947-6539 .- 1521-3765. ; 21:22, s. 8168-8176
-
Tidskriftsartikel (refereegranskat)abstract
- The electron-accepting ability of 6,6-dicyanopentafulvenes (DCFs) can be varied extensively through substitution on the five-membered ring. The reduction potentials for a set of 2,3,4,5-tetraphenyl-substituted DCFs, with varying substituents at the para-position of the phenyl rings, strongly correlate with their Hammett sigma(p)-parameters. By combining cyclic voltammetry with DFT calculations ((U)B3LYP/6-311+G(d)), using the conductor-like polarizable continuum model (CPCM) for implicit solvation, the absolute reduction potentials of a set of twenty DCFs were reproduced with a mean absolute deviation of 0.10eV and a maximum deviation of 0.19eV. Our experimentally investigated DCFs have reduction potentials within 3.67-4.41eV, however, the computations reveal that DCFs with experimental reduction potentials as high as 5.3eV could be achieved, higher than that of F-4-TCNQ (5.02eV). Thus, the DCF core is a template that allows variation in the reduction potentials by about 1.6eV.
|
|
| 3. |
|
|
