The maximum file name length for OUTFILE= in the EXPORT procedure and for DATAFILE= in the IMPORT procedure is limited to 201 characters. 
Specifying a path with more than 201 characters generates the following ERROR in the log:

ERROR: File Name value exceeds maximum length of 201 characters.

To specify more than 201 characters in a path, issue a FILENAME statement prior to the PROC EXPORT or PROC IMPORT step. 
Use the FILEREF for the OUTFILE= in PROC EXPORT or the FILEREF for the DATAFILE= in PROC IMPORT.