3-IODOCINNAMIC ACID synthesis

Yield:41070-12-6 93%

Reaction Conditions:

with trans-N,N'-dimethylcyclohexane-1,2-diamine;1,1,1,3,3,3-hexamethyl-disilazane;sodium iodide;copper(l) iodide in 1,4-dioxane at 110; for 22 h;

Steps:

74 Example [74]; Preparation of 3-iodocinnamic acid through an in situ generated [TRIMETHVLSILYL] ester

A Schlenk tube was charged with Cul (9.6 mg, 0.050 mmol, 5.0 mol%), 3- bromocinnamic acid (228 mg, 1.00 mmol), NaI (300 mg, 2.00 mmol), evacuated and backfilled with argon. Racemic trans-N,N'-dimethyl-1, 2-cyclohexanediamine (16 μL, 0.10 mmol, 10 mol%), 1,1, 1,3, 3, [3-HEXAMETHYLDISILAZANE] (211 [I1L,] 1.00 mmol), and dioxane (1.0 mL) were added under argon. The Schlenk tube was sealed with a Teflon valve and the reaction mixture was stirred at [110 °C] for 22 h. The resulting suspension was allowed to reach room temperature, poured into ether (20 mL), and washed with a solution of Na2S205 (100 mg) in 10% aq [HC1] [(3X20] mL). The organic phase was dried [(NA2SO4)] and concentrated. The residue was dissolved in hot ethanol (5 mL), and hot water (5 mL) was added to the solution. The product was allowed to crystallize at 0 [C] for 15 h to provide 256 mg (93% yield) of 3-iodocinnamic as pale yellow needles. Mp: [186-188 °C] (lit. 180- [182 °C] See Yuzikhin, [O.] S.; Vasil'ev, A. V.; Rudenko, A. P. [RUSS. J ORG. CLIENI.] 2000, 36, [1743). 1H] NMR (400 MHz, DMSO-d6): 8 12.47 (s, 1H), 8.08 (s, 1H), 7.77 (d, J= 7.8 Hz, 1 H), 7.72 (d, [J=] 7.8 Hz, [1H),] 7.52 (d, [J=] 16.0 Hz, 1 H), 7.22 (t, [J= 7.] 8 Hz, [1H),] 6.5 8 (d, J = 16.0 Hz, 1H). [13C] NMR (100 MHz, DMSO-d6) : 8 167.3, 142.3, 138.6, 136.6, 136.5, 130.9, 127.4, 120.6, 95.4.

References:

WO2004/13094,2004,A2 Location in patent:Page 81