Hydrocarboxylation of alkene

several conditions available.
1. Pd /ligand /CO/MeOH/TsOH or MsOH
elevated temp, CO >1 atm,
if you have a isopropyl group on the terminal, then ester adds to the 2-carbon!
2. Ru2(CO)12

internal alkene can be isomerized and forms terminal carboxylate.