1: (4S,5R)-1-benzyl-4-hydroxy-5-thiophenol-2-pyrrolidinone With n-butyllithium; naphthalenyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: methanol in tetrahydrofuran; hexane T=-78 - 0°C; Carbonylation;

1: (4S,5R)-1-benzyl-4-hydroxy-5-thiophenol-2-pyrrolidinone With n-butyllithium; naphthalenyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: methyl iodide in tetrahydrofuran; hexane T=-78 - 0°C; Addition;

1: (4S,5R)-1-benzyl-4-hydroxy-5-thiophenol-2-pyrrolidinone With n-butyllithium; naphthalenyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: acetone in tetrahydrofuran; hexane T=-78 - 0°C; Carbonylation;

1: (4S,5R)-1-benzyl-4-hydroxy-5-thiophenol-2-pyrrolidinone With n-butyllithium; naphthalenyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: cyclohexanone in tetrahydrofuran; hexane T=-78 - 0°C; Addition;

1: (4S,5R)-1-benzyl-4-hydroxy-5-thiophenol-2-pyrrolidinone With n-butyllithium; naphthalenyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: benzaldehyde in tetrahydrofuran; hexane T=-78 - 0°C; Addition;

1: (4S,5R)-1-benzyl-4-hydroxy-5-thiophenol-2-pyrrolidinone With n-butyllithium; naphthalenyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: 4-methoxy-benzaldehyde in tetrahydrofuran; hexane T=-78 - 0°C; Addition;