Process for the preparation of 2,2,3,3-tetrafluoro-1,4-benzodioxanes, novel o-(2-bromo-1,1,2,2-tetrafluoroethoxy)-phenols, and novel 2-bromo-1,1,2,2-tetrafluoroethoxy-containing phenyl ethers

Granted: Aug 10, 1999 Filed: Jul 23, 1998

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.