You can do it with a macro
Code:
Sub AddHLink()
Dim oRng As Range
Dim strLink As String
Set oRng = ActiveDocument.Range
With oRng.Find
Do While .Execute(FindText:="([A-Z]{2}) ([0-9]{4,}) ([A-Z0-9]{1,2})", MatchWildcards:=True)
strLink = oRng.Text
strLink = Replace(strLink, Chr(32), "")
strLink = "https://www.google.co.in/patents/" & strLink & "?cl=en \t _blank"
oRng.Text = ""
ActiveDocument.Fields.Add oRng, wdFieldHyperlink, strLink, False
oRng.Fields.Update
oRng.Collapse 0
Loop
End With
lbl_Exit:
Set oRng = Nothing
Exit Sub
End Sub
http://www.gmayor.com/installing_macro.htm