$list1={{c11,c12},{c21,c22},{c31,c32}};
$list2={b1,b2,b3};

mapFirst[first_,second_]:=somefunc[#,second]&/@first;
MapThread[mapFirst,{$list1,$list2}]
%//MatrixForm

Outer[somefunc,$list1,$list2,{1}]
%//MatrixForm

MapThread[Distribute[somefunc[#1,#2]&,List],{$list1,$list2}]

(Pi*3^2)*6/2+(Pi*3^2)*4