2,3-dimethoxy-[1,3]dioxolo[4',5':4,5]benzo[1,2-c]phenanthridine (Nornitidine) (3)
Following the general procedure, from triflate 6 (93 mg) and
amine 7 (64 mg), 62 mg were obtained as solid (72%).
Spectral data corresponds to those reported in the literature.5
!H NMR (300 MHz, CDCl3): ! (ppm) 9.33 (s, 1H), 8.65 (d,
1H, J = 9.0 Hz), 8.56 (s, 1H), 8.18 (s, 1H), 7.97 (d, 1H, J =
9.0 Hz), 7.73 (s, 1H), 7.53 (s, 1H), 6.22 (s, 2H), 4.10 (s, 3H), 3.99 (s, 3H). 13C NMR (75.4
MHz, CDCl3): ! 153,3, 149.7, 149,6, 148.0 (x2), 138.4, 129.3, 128.4, 127.9, 126.4, 121.8, 119.8,
119.2, 107.8, 104.5, 102.4, 101.4, 100.9, 56.2, 55,7.
[1,3]dioxolo[4',5':4,5]benzo[1,2-c][1,3]dioxolo[4,5-j]phenanthridine (Noravicine) (4)
Following the general procedure from the triflate 6 (93 mg)
and the amine 8 (60 mg), 61 mg were obtained as solid (74%).
Spectral data corresponds to those reported in the literature.6
!H NMR (500 MHz, CDCl3): ! (ppm) 9.29 (s, 1H), 8.55 (s,
1H), 8.53 (d, 1H, J = 9,2 Hz), 8.34 (s, 1H), 7.95 (d, 1H, J = 9.2
13
Hz), 7.70 (s, 1H), 7.52 (s, 1H), 6.29 (s, 2H), 6.22 ppm (s, 2H). C NMR (75.4 MHz, CDCl3): !
151.8, 149.7, 148.1, 147.9, 141.9, 130.5, 129.6, 129.4, 126.7, 123.1, 122.4, 120.3, 119.2, 104.9,
104.6, 102.2, 101.5, 101.0, 100.1.
Synthesis of triflates:
General procedure for the synthesis of epoxynaphtalenes : A dried round-bottom flask was
charged with the corresponding dibromoaryl (16.89 mmol, 1 eq) and furane (84.47 mmol, 5 eq)
in dry toluene (50 ml) under argon atmosphere. The solution was cooled at -78 ºC and n-BuLi
1.6M in THF (18.58 mmol,1.1 eq) was added dropwise to the solution. After complete addition,
the solution was warmed up to -40ºC and extracted with EtOAc (3x20 ml), dried over
magnesium sulfate and concentrated under vacuum. The residue was purified by
chormatography column (EtOAc/heptane).
1,4-dihydro-6,7-dimethoxy-1,4-epoxynaphtalene (9)
Following the general procedure, from 4,5-dibromoveratrol (5 g), 1.91 g
of 9 (56% yield) were obtained as a white solid, the product is
spectroscopically identical to the material described in the literature.7
!H-NMR (500 MHz, CDCl3): $ (ppm) 7.01 (s, 21H), 6.94 (s, 21H), 5.65
(s, 21H), 3.82 (s, 6H).
5,8-dihydro-5,8-epoxynaphto[2,3-d][1,3]dioxo (10)
Following the general procedure, from 5,6-dibromo-1,3-benzodioxole
(4.73 g) were obtained 3.17 g of 10 (81% yield) as a white solid, the
product is spectroscopically identical to the material described in the
literature.1 !H-NMR (300 MHz, CDCl3): $ (ppm) 7.07 (s, 2H), 6.86 (s, 2H), 5.96 (d, 1H, J = 1.4
Hz), 5.91 (d, 1H, J = 1.4 Hz), 5.66 (s, 2H).
General procedure for the synthesis of alcohols: To a solution of the corresponding
epoxynaphtalene (7.35 mmol) in DCE (50 ml) was added at 0°C and dropwise a solution of p-
toluenesulfonic acid (1.47 mmol, 0.2 eq.) in DCE (2 ml). The reaction mixture was stirred at r.t.
overnight. The mixture was diluted with DCM, washed with water and brine, dried over
magnesium sulfate and concentrated under vacuum. The products were used for the next step
without further purification.
S3