Where a lone pair from the nucleophile overlaps Using the sigma* orbital on the leaving group. Even so, this phase does not hold the same sensitivity to steric hindrance given that the SN2 reaction, as we are about to see. On the other hand, the proof concerning their efficacy is https://edwinoanzk.ampblogs.com/5-simple-techniques-for-solution-bromure-de-potassium-74314981