Sub SaveAllOpenDocsAsPDF()
Set fs = CreateObject("Scripting.FileSystemObject")
locFolder = InputBox("Enter the folder path to DOCs", "File Conversion", "C:\myDocs")
Set oFolder = fs.GetFolder(locFolder)
For Each oFile In oFolder.Files
    Set aDocument = Application.Documents.Open(oFile.Path)
    aDocument.SaveAs FileName:=aDocument.FullName & ".pdf", FileFormat:=wdFormatPDF
    aDocument.Close SaveChanges:=wdDoNotSaveChanges
Next oFile
End Sub