The reaction yields were subsequently predicted on a much larger chemical space with the established prediction model, including 12642 pairs of combinations (86*147, 86 types of alkenes and 147 types of electrophiles, see Supplementary Fig. ). Fig. shows several recommended substrates (6 alkenes and 15 electrophiles), which might exhibit high reactivity. One can see that in addition to halogenated arenes, aromatic heterocycles might also be suitable electrophiles. Based on machine-learning-assisted predictions, we investigated the reactivity of aromatic heterocycles experimentally. We were delighted to find that even challenging aromatic heterocycles, such as pyridine, quinoline, and isoquinoline, 1,5-naphthyridine, pyrazine, and 5H-1-pyrindene are effective coupling partners (via direct C-H substitution), providing the desired products 4, 29, 49-50, 73-76 in moderate to good yields and excellent site-selectivity under slightly different reaction conditions (as shown in Fig. ).