This is straight from my solly cfg and it works fine.
// Rocket Launcher
alias "+rockets" "slot1;+attack"
alias "-rockets" "-attack;+reload"
// Shotgun
alias "+shotty" "slot2;+attack"
alias "-shotty" "-attack;+reload;"
// Equalizer
alias "+pick" "slot3;+attack;r_drawviewmodel 1"
alias "-pick" "-attack"
bind "mouse1" "+rockets"
bind "mouse2" "+shotty"
bind "mouse3" "+pick"