with the formation of

with the formation of
原句为：The synthetic sequence described contains firstly a Knoevenagel condensation of 3 and 4 with 11 with the formation of
the 1,3-oxabutadienes 14 and 15,respectively,which then undergo a facial-differentiating hetero-Diels ± Alder reaction with the enol ethers 12 and 13.
里面这个with the formation