C-IMIDAZO[1,2-A]PYRIDIN-3-YL-METHYLAMINE

General procedure: To asolution of 1 g (2.7 mmol) of 10 in 20 ml of DCM was added 1.2 ml(8.1 mmol) of TEA. This solution stirred at room temperature for15 min followed by the addition of TBTU (0.82 g, 3.3 mmol). Theresulting mixture stirred for 15 min, and 3.3 mmol of the corresponding(heterocyclylmethyl)amine 7 was added. The reactionmixture was washed with a 10% aqueous solution of potash andwater. The organic layer was dried over sodium sulfate and evaporatedon a rotary evaporator. Diethyl ether was added to the residue, and the resulting precipitatewas filtered and dried in vacuo. Atotal of 1.8 mmol of 8 was dissolved in a mixture of 18 ml of THF and2 ml of methanol, 0.09 g of 10% Pd/C was added, and the mixturestirred under a hydrogen atmosphere for 8 h. The reaction mixturewas passed through Celite and the filtrate was evaporated. Theresidue was stirred with ether, filtered and dried in vacuo.A mixture of ethyl 5-bromo-3-phenylpentanoate a56 (synthesized as descibed by Burger and Hofstetter in J. Org. Chem. (1959), 24, 1290); 0.425 g, 1.49 mmol), 1-imidazo[1 , 2- a]pyridin-3-ylmethanamine a54 (0.329 g, 2.24 mmol), and anhydrous CS2CO3 (0.329 g, 2.24 mmol) in absolute MeCN (6 ml.) is refluxed under stirring in the absence of air moisture for 5 h, cooled to room temperature, filtered, and evaporated. The residue (0.57 g) is purified twice by chromatography on silicagel (eluent 1 : CHCl3/MeOH 20/1 v/v; eluent 2: AcOEt/acetone 1/1 v/v). The obtained fraction is dissolved in THF (0.5 ml.) and 4 M HCI in dioxane (0.15 ml.) is added to the obtained solution to give, after fitration, 1- (imidazo[1 , 2-a]pyridin-3-ylmethyl)-4-phenylpiperidin-2-one hydrochloride 24 (0.082 g) as a solid. Yield: 16 %. LC-MS (MH+): 3061-imidazo[1 , 2-a]pyridin-3-ylmethanamine a54 (197 mg, 1.33 mmol) and Ti(O-/-Pr)4(0.713 mL, 2.37 mmol) are added to a solution of ethyl 5-oxo-4-phenylpentanoate a53 (see Ledon H. et al., Bull. Soc. Chim. Fr. (1973), 2071-2076; 294 mg, 1.33 mmol) in dichloromethane (2.5 mL) under stirring in argon. The reaction mixture is stirred at room temperature for 3.5 h, and an additional portion of Ti(O-/-Pr)4 (0.08 mL, 0.37 mmol) is added. After 40 min., the mixture is evaporated under reduced pressure. The residue is dissolved in absolute methanol (6 mL), and NaBH4 (81 mg, 2.1 mmol) is added in portions under stirring. After 15 min., a 0.1 N NaOH solution (5 mL) is added, and the mixture is additionally stirred for 15 min. and many times subjected to extraction with dichloromethane. The combined organic extracts are dried over anhydrous Na2SO4 and evaporated to afford an oily residue (466 mg). According to the LC-MS data, this residue mainly consisted of the mixture of methyl, ethyl, and isopropyl esters a55. The residue is dissolved in toluene (10 mL) and refluxed for 9 h. The reaction mixture is cooled to room temperature and evaporated under reduced pressure. The residue (459 mg) is purified by

Molecular Weight:147.18
XLogP3:0.7
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:1
Exact Mass:147.079647300
Monoisotopic Mass:147.079647300
Topological Polar Surface Area:43.3
Heavy Atom Count:11
Complexity:137
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes