Multi-step reaction with 7 steps
1.1: diisobutylaluminium hydride / dichloromethane; toluene / 1 h / -78 °C / Inert atmosphere
1.2: 2 h / -78 - 20 °C / Inert atmosphere
2.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / 1 h / -78 °C / Inert atmosphere
2.2: 0.67 h / -78 - 20 °C / Inert atmosphere
3.1: (2R,5R)-(+)-2-tert-butyl-3-methyl-5-benzyl-4-imidazolidinone; diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate; trifluoroacetic acid / chloroform / 72 h / -30 °C / Inert atmosphere
4.1: toluene / 3 h / -78 °C / Inert atmosphere; Molecular sieve
4.2: 2 h / -78 - 20 °C / Inert atmosphere
5.1: tetra-(n-butyl)ammonium iodide; N-ethyl-N,N-diisopropylamine / dichloromethane / 24 h / 0 - 40 °C / Inert atmosphere
6.1: dimethylsulfide borane complex / tetrahydrofuran / 6 h / 0 - 20 °C / Inert atmosphere
6.2: 2 h / 0 - 20 °C / Inert atmosphere
7.1: di-isopropyl azodicarboxylate; triphenylphosphine / tetrahydrofuran / 19 h / 0 - 20 °C / Inert atmosphere
With
(2R,5R)-(+)-2-tert-butyl-3-methyl-5-benzyl-4-imidazolidinone; oxalyl dichloride; di-isopropyl azodicarboxylate; dimethylsulfide borane complex; diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate; tetra-(n-butyl)ammonium iodide; diisobutylaluminium hydride; dimethyl sulfoxide; N-ethyl-N,N-diisopropylamine; triphenylphosphine; trifluoroacetic acid;
In
tetrahydrofuran; dichloromethane; chloroform; toluene;
2.1: Swern oxidation / 2.2: Swern oxidation / 4.1: Roush crotylation / 7.1: Mitsunobu reaction;
DOI:10.1016/j.tet.2011.06.025