The present disclosure provides tri-orthoalkylphenyl phosphine catalysts of formula I ##STR00001## wherein A is CH2, CO, or NR.sup.A; R.sup.1 is aryl, heteroaryl, isopropyl, tert-butyl, cycloalkyl, or heterocycloalkyl, wherein aryl, heteroaryl, cycloalkyl and heterocycloalkyl are optionally substituted; R.sup.2 is H, (C.sub.1-C.sub.8)alkyl, (C.sub.1-C.sub.8)alkoxy, N(R.sup.A).sub.2, or an electron withdrawing group; and each R.sup.A is independently H or (C.sub.1-C.sub.8)alkyl; that are tuned electrically and sterically.

The present disclosure provides tri-orthoalkylphenyl phosphine catalysts that are tuned electrically and sterically. Method of using the catalyst for cross-coupling of unactivated secondary boronic acids with near-perfect levels of site- and stereoretention are also provided.