After this common joseki- you might think white can go to the 2-2 point. This is actually an overplay.
(;C[The triangle stone is an overplay by white. Black to cut off and kill it.]AB[pd]AB[qc]AB[nd]AW[qf]AW[rd]AW[qi]AW[rb]TR[rb]AP[goproblems];B[rc];W[sc]
(;B[re];W[qe];B[qd];W[sd]
(;B[sb];W[sa];B[se];W[sb];B[qb]C[Correct! Note that white could have fought a ko here for the connectionRIGHT])
(;B[se];W[sb];B[qb];W[rf];B[ra];W[sf]))
(;B[qb];W[sb];B[re];W[qe];B[qd];W[sd]
(;B[ra];W[rf])
(;B[se];W[rf];B[ra];W[sf])))