This method could also be used to obtain the two amino (or acylamino) group substituted alkynes Z-B-3 with ketene imines B-INT3A-1 and silyl-imine INT3B as substrates (scheme 3b). The regio-selectivity get rather complicate. In this case, the steric-effect of R7 and R2, and steric effect of R6 and R4 together determine the ΔG of cis-configuration transition state Z-B-TS4. Similarly, steric effect between R6 and R2, and steric effect between R7 and R4 together determines the ΔG of the trans-configuration transition state E-B-TS4. Our calculations reveal that when N-acetylsubstituted ketene imines B-int3a-1 and TMS-substituted imine TMS-INT3b is used as model substrate, the regioselectivity is reduced compared with previous example (cisselectivity vs trans-selectivity = 9.0 kcal/mol vs 11.4 kcal/mol, see details in SI, figure ).