Upvote:3
In principle, no, as explained in earlier questions (e.g. Should my first trip be to the country which issued my Schengen Visa?) you should really apply to the country that will be your main destination and the German consulate shouldn't issue the visa without authorization from Belgium. However, if there is no Belgian consulate in your country, there are still two things you could do:
Details about all this can be found on pp. 19-23 of the Handbook for the processing of visa applications and the modification of issued visas