Syntax error..

First of all lemme mention that this is not HOMEWORK.
One of r clients have switched server from FTP to sFTP.
Hence,
I've been asked to modify the following command by piping it with a PRINT so as to avoid exposing the password.
sftp -B /dev/fd/0 $USERSTRING@$FTPSVRSTRING << EOF 1>>$LOG_FILE 2>>$LOG_FILE1

No matter what ever I'm trying it is giving me syntax error.
Can someone pls give me the correct syntax for this.