CYTISINE synthesis

Yield:-

Steps:

Multi-step reaction with 11 steps
1.1: (-)-B-methoxydiisopinocampheylborane / diethyl ether / 1.25 h / -78 - 20 °C
1.2: diethyl ether / -78 - 20 °C / Acid hydrolysis
1.3: 76 percent / aq. NaOH; aq. H₂O₂ / 3 h / Heating
2.1: 99 percent / Et₃N; DMAP / CH₂Cl₂ / 1.5 h / 20 °C
3.1: 87 percent / NaN₃ / dimethylformamide / 2 h / 80 °C
4.1: Ph₃P / tetrahydrofuran
4.2: 66 percent / H₂O
5.1: 89 percent / Et₃N; DMAP / CH₂Cl₂ / 4.5 h / 0 - 20 °C
6.1: 79 percent / Cl₂Ru(CHPh)(PCy₃)2 / CH₂Cl₂ / 12 h / Heating
7.1: 98 percent / NaOH / tetrahydrofuran / 2 h / 20 °C
8.1: 67 percent / Et₃N; DMAP / CH₂Cl₂ / 1.5 h / 20 °C
9.1: 89 percent / NaH / tetrahydrofuran / 0 - 20 °C
10.1: 50 percent / DDQ / dioxane / 4 h / 110 °C
11.1: 78 percent / HCl / tetrahydrofuran / 3 h / Heating

References:

Danieli, Bruno;Lesma, Giordano;Passarella, Daniele;Sacchetti, Alessandro;Silvani, Alessandra;Virdis, Andrea [Organic Letters,2004,vol. 6,# 4,p. 493 - 496]

FullText