the wonderful yet vague synth on Rhodium's page has what looks to be a an chemical error on it. Since we are attmepting the conjugate addition of an alkyl group (our chloro-phenyl guy) we would want to use a lithium diorganocopper reagent wouldn't we? Using the straight up grignard would lead to direct carbonyl addition on our ester producing something funky, don't you agree Rhodium?
Edit: The link for the procedure is https://www.thevespiary.org/rhodium/Rhodium/chemistry/cocaine.analog.arecoline.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/cocaine.analog.arecoline.html)