8. Conclusion

Our society has become aware of the waste problem as it exists today. A radical change of attitude is taking place: rather than treating the waste produced, we need to reduce it at source to prevent pollution. Many disciplines need to be involved in this reduction effort, including chemistry. In this way, prevention must come first, avoiding the need to treat or even recover waste. The main objective in organic synthesis is to produce a desired compound by simply mixing all the starting components with, if necessary, the presence of a catalytic amount of external reagents and with a minimum loss of atoms [147]. RCMs in general, and IMCR in particular, intrinsically satisfy the criteria of green chemistry and will play an increasingly important role in the various fields of chemistry.

Of course, it's impossible to synthesize every molecule in a single step. Nevertheless,...