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Proofreading experimentally assigned stereochemistry through Q2MM predictions in Pd-catalyzed allylic aminations

ABSTRACT: The palladium-catalyzed enantioselective allylic substitution by carbon or nitrogen nucleophiles is a key transformation that is particularly useful for the synthesis of bioactive compounds. Unfortunately, the selection of a suitable ligand/substrate combination often requires significant screening effort. Here, we show that a transition state force field (TSFF) derived by the quantum-guided molecular mechanics (Q2MM) method can be used to rapidly screen ligand/substrate combinations. Testing of this method on 77 literature reactions revealed several cases where the computationally predicted major enantiomer differed from the one reported. Interestingly, experimental follow-up led to a reassignment of the experimentally observed configuration. This result demonstrates the power of mechanistically based methods to predict and, where necessary, correct the stereochemical outcome. A predictive model has been created for a stereoselective palladium-catalysed allylic amination reaction. Derived only from quantum chemical data, the method is accurate enough to reveal multiple erroneous assignments in literature experiments.

SUBMITTER: Wahlers J

PROVIDER: S-EPMC8602308 | biostudies-literature |

REPOSITORIES: biostudies-literature

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