| abstract |
A compound having structural formula (II): where R2 is H, CH3, CF3, CH2CF2CF2H, or CH2CF2CF2CF2CF2H; where R2f is a perfluoroalkyl group having 1-4 carbon atoms, optionally comprising either or both of a catenated nitrogen heteroatom and a catenated oxygen heteroatom; where R2f' is CF3 or CF2CF3; and where R2f" is CF3 or CF2CF3; with the proviso that when R2f' is CF3, then R2f" is CF3, and when R2 is H or CH3, then R2f is not CF3. |