Multi-step reaction with 19 steps
1: n-BuLi / tetrahydrofuran / -85 - 20 °C
2: 61 percent / HClO4 / tetrahydrofuran; H2O
3: 91 percent / Et3N; DMAP / CH2Cl2
4: 74 percent / PPTS / butan-2-one / Heating
5: 96 percent / imidazole / dimethylformamide
6: 97 percent / PPTS / CH2Cl2
7: 85 percent / TBAF / tetrahydrofuran / -40 °C
8: 98 percent / K2CO3 / methanol
9: DIAD; PPh3 / toluene
10: pyridine
11: CsF / dimethylformamide / 60 °C
12: imidazole / dimethylformamide / 50 °C
13: 91 percent / K2CO3 / methanol
14: 93 percent / PPTS / methanol
15: 90 percent / PPTS / dimethylformamide
16: 96 percent / H2O; KOH / tetrahydrofuran; methanol
17: 75 percent / EDC*HCl; DMAP / CH2Cl2
18: 99 percent / imidazole / dimethylformamide
19: 45 percent / CuI; i-Pr2NEt / Pd2(dba)3*CHCl3 / dimethylformamide / 0.5 h / 20 °C
With
pyridine; 1H-imidazole; dmap; potassium hydroxide; copper(l) iodide; n-butyllithium; perchloric acid; di-isopropyl azodicarboxylate; tetrabutyl ammonium fluoride; water; pyridinium p-toluenesulfonate; potassium carbonate; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine; N-ethyl-N,N-diisopropylamine; triphenylphosphine; cesium fluoride;
tris(dibenzylideneacetone)dipalladium(0) chloroform complex;
In
tetrahydrofuran; methanol; dichloromethane; water; N,N-dimethyl-formamide; toluene; butanone;
1: Addition / 2: Ring cleavage / 3: Acetylation / 4: ether cleavage; rearrangement / 5: silylation / 6: Addition / 7: desilylation / 8: Deacetylation / 9: Cyclization / 10: Acetylation / 11: Addition / 12: silylation / 13: Deacetylation / 14: ether cleavage / 15: Substitution / 16: Hydrolysis / 17: Esterification / 18: silylation / 19: Sonogashira coupling;
DOI:10.1016/S0040-4039(99)01744-X