How to separate a list of molecules based on how many hydrogens are attached to a certain atom?

I have alkene molecules of formula C9H17B. How can I separate these molecules into three classes, one being the class that has C-B-H2, one that has C2-B-H and one that has C3-B. How would I do this? I've tried using smiles and also as mol but my approaches aren't working.

To find specific substructures use SMARTS.

https://www.daylight.com/dayhtml/doc/theory/theory.smarts.html

If I see it correctly these are the three types of boron you are looking for.

from rdkit import Chem
from rdkit.Chem import Draw

smiles = ['CCB', 'CCBC', 'CCB(C)(C)']

mols = [Chem.MolFromSmiles(s) for s in smiles]
Draw.MolsToGridImage(mols)

Write SMARTS for boron with three connections BX3 and number of hydrogen H2, H1, H0.

smarts = ['[BX3;H2]', '[BX3;H1]', '[BX3;H0]']
patts = [Chem.MolFromSmarts(s) for s in smarts]

Now you can proof for substructure in each molecule.

for p in patts:
    for m in mols:
        print(m.HasSubstructMatch(p))
    print()

True
False
False

False
True
False

False
False
True