[2-(4-AMINO-PHENYL)-ETHYL]-CARBAMIC ACID TERT-BUTYL ESTER

To a solution of [2-(4-nitro-phenyl)-ethyl]-carbamicacid te/t-butyl ester (18.7 g, 70.30 mmol) in ethanol (200 ml) a slurry of 10percent palladium on charcoal (2 g) in water (10 ml) was added. At 80STEP 2. tert-butyl 2-(4-aminophenyl)ethylcarbamate General Procedures for the syntheses of aminesGeneral procedure AP: Boc protection of long and short chain amino anilinesTo a stirred solution of amine (1.0 eq), TEA (2 eq) in DCM (25 vol) was added di-tert-butyl dicarbonate, (1.1 eq). The mixture was stirred overnight at ambient temperature. The mixture was concentrated in vacuo and purified by FCC eluting with EtOAc :Heptane, 1 :3.; tert-Xi\ty\ [2-(4-aminophenyl)ethyl] carbamate I ntlThe title compound was prepared according to general procedure AP using 2-(A- aminophenyl)ethylamine (1.0 g, 7.3 mmol), TEA (2 mL, 14 mmol), DCM (25 mL), and di- tert-butyl dicarbonate (1.7 g, 7.7 mmol). The title product was obtained as a white solid. No further purification was required. Yield: 1.6 g, 92 percent.A solution of 2-aminoethylaniline (5.0 g) and Boc- Preparation of tert-Butyl (4~aminophenethyl)carbamate. 4-(2-aminoethyl)aniline (5.00 grams, 36.7 mmol, 1.0 eq) was dissolved in 50 mL EtOAc and placed in a water bath. To the rapidly stirring solution, a mixture of boc anhydride (8.25 grams, 37.8 mmol, 1.03 eq) in 50 mL EtOAc was added dropwise. Upon addition of the anhydride, the mixture turned into a white slurry, which after 4 hours became a pale yellow clear solution. Reaction left overnight. The crude mixture was concentrated under reduced pressure to a pale yellow oil, diluted with 10 mL hot EtOAc and mixed with 50 mL hot heptane. The mixture was placed in an ice bath to facilitate precipitation. The white crystals were filtered and dried to yield 7.11 grams (82percent). 1H NMR (400 MHz, DMSO-d6) δ 6.82 (d, J= 7.8 Hz, 2H), 6.76 (s, 1H), 6.47 (d, J= 7.8 Hz, 2H), 4.82 (s, 2H), 3.02 (q, J= 6.4 Hz, 2H), 2.47 (m, 2H), 1.37 (s, 9H).Step 1: [2-(4-Amino-phenyl)-ethyl]-carbamic acid tert-butyl ester; To a solution of 4-aminophenethylamine (0.136 g, 1 mmol) in dichloromethane (4 mL) at rt was added ( Alternative Preparation of (R)-N2- [4- (2-AMINOETHYL) PHENYL]-L- phenylethane-1, 2-diamine; a. Preparation of [2- (4-AMINOPHENYL) ethyl] carbamic acid TERT-BUTYL ester; To a suspension of 4-aminophenethylamine (65.1 g, 1.0 equiv) in dichloromethane (1.5 L) at 0 °C was added di-tert-butyl dicarbonate (99.2 g, 0.95 equiv) in dichloromethane (300 ML) dropwise. The solution was slowly warmed to room temperature and stirred for 18 hours. Water (200 mL) was added, solvents were evaporated under reduced pressure to a volume of approximately 1L, the aqueous and organic layers were separated, and the organic layer was washed with water (200 mL) followed by saturated aqueous sodium chloride (100 mL). The organic layer was dried over anhydrous sodium sulfate (40 g). The solids were filtered and the filtrate concentrated to give crude title intermediate (100.7 g) which was suspended in a mixture of hexanes (745 mL) and ethyl acetate (150 ML). The slurry was heated until a clear solution was obtained and then the solution was slowly cooled to room temperature. The resulting cystals were filtered, washed with 10 percent ethyl acetate/hexanes solution (100 ML) and dried under vacuum to provide the title intermediate (55.1 g, 48 percent yield).Di-tert-butyl-dicarbonate (1.60 g, 7.34 mmol) was added to a solution of 2-(4-aminophenyl)ethylamine (1.00 g, 7.34 mmol) in EtOAc (20 mL) at rt. After stirring for 18 h, the reaction was washed with 10percent NaHCO[2-(4-Amino-phenyl)-ethyl]-carbamic acid tert-butyl ester (Y-1).

Molecular Weight:236.31
XLogP3:2.2
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:5
Exact Mass:236.152477885
Monoisotopic Mass:236.152477885
Topological Polar Surface Area:64.4
Heavy Atom Count:17
Complexity:240
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes