Parallel coordinates plots of individual clusters are shown in Figure . Their characteristics, summarized in Table , illustrate the diversity of high quality samples. In this table, the material cost and yield are omitted, because the behaviors of material cost and E-factor is about the same and there is no almost change in the yield. Due to low E-factor, cluster 1 and 4 provide environmentally friendly solutions, while clusters 2 and 3 are not favorable in this aspect. The space time yield of cluster 4 is much better than cluster 1, which is achieved by the highest reactant concentration, high temperature, and short residence time.