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.
具有结构式(II)的化合物:其中R2为H、
CH3、
CF3、
CH2CF2CF2H或
CF2CF2CF2CF2H;其中R2f为具有1-4个碳原子的
全氟烷基基团,可选地包括串联的氮杂原子和/或串联的氧杂原子中的任一种或两种;其中R2f'为 或
CF2 ;其中R2f"为 或
CF2 ;但是当R2f'为 时,R2f"为 ,当R2为H或 时,R2f不是 。