I usually locate hotels, restaurants and other sites in Paris by their metro stop. It appears that L' Institut Catholique de Paris is in the 6th near the Sainte-Placide and Rennes metro stops. The closest hotel that I recognize near there is the Hotel Lutetia. It is a gorgeous, formal, ornate building - part Art Deco and part Art Nouveau. In fact, I believe that the top German officers stayed there during WWII. But it is a five star hotel and very expensive. I don't think it is what you are looking for.

Slightly further away are 2 three-star hotels that I can recommend - Hotel de Varenne, 44 rue de Bourgogne, 7th http://www.varenne-hotel-paris.com/english/the-hotel.html Both Ziner John in San Diego and I have stayed here and can personally vouch for its quality. A quiet location with nice rooms and a lovely patio where you can eat breakfast on spring mornings.

Hotel de l'Odeon, 13 rue Saint-Sulpice, 6th http://www.paris-hotel-odeon.com/english/Main.htm The favorite Paris hotel of a world-travelling friend of mine. She always stays there when she visits Paris.

Have a great trip! By the way, since you said that you will be there in May, remember that May 1 (Worker's Day or Labor Day) and May 8 (VE Day) are holidays. Shops, restaurants and museums may be closed.

Cheers, Mark in Los Angeles