Not A Good Idea: While using Analogous colors that sit next to each other look nice, colors used this way are not very functional. For example, it’s nearly impossible to identify a specific color of a label shown. If using a Legend, how do you easily identify which Label matches which slice?
With color harmony in mind and using just a simple chart you can put more emphasis on the data shown. Using colors, you could help the viewer to distinguish the information easier as well as guide their eye to a certain area of a chart that you want to focus on.