1-Adamantanecarboxaldehyde was synthesized according to literature 8 : 5.57 mL (64.96 mmol, 1.2 equiv.) oxalyl chloride was added to 60 mL DCM cooled to -94 º C (acetone/N2 bath) and 9.23 mL (129.9 mmol, 2.4 equiv.) DMSO in 30 mL DCM were added slowly over 30 min to the mixture and stirred for 15 min before 1 equivalent of 1-adamantanemethanol in 90 mL DCM was added over 20 min and stirred for another 15 min. Afterwards, 30 mL (216.5 mmol, 4 equiv.) NEt3 was added and stirred for 2.5 h at 0 º C. The reaction was quenched by adding 100 mL H2O, and the water phase was extracted twice with DCM. The organic layers were extracted with water, brine, and water again and dried over Mg2SO4, filtered, and evaporated to give 8.15 g (92%) as a white powder. The product was used without further purification for the next step. Two equivalents of 2-acetylpyridine (6.54 mL, 0.058 mol) were added to a mixture of 2 equiv. KOtBu (6.51 g, 0.058 mol) in 160 mL THF and 1. equiv. of 1-adamantane carboxaldehyde (4.79 g, 0.029 mol) was added, and the red mixture was stirred for 4 h at RT. Afterwards, 22.35 g (0.29 mol) ammonium acetate dissolved in 100 ml glacial acetic acid was added, and the mixture was refluxed (105 ºC) for 16h. The solvent was evaporated to give a brown-yellow residue which was neutralized with saturated NaHCO3 solution to a pH 6-7. Afterwards, diethyl ether was added. The water phase was washed with diethyl ether to give a yellow mixture in Et2O. The organic layer was washed three times with (each 100 mL) H2O. The organic layers were combined, dried over Mg2SO4, filtered, and evaporated to give a yellow-brown residue. The mixture was packed on an Al2O3 column in Et2O/hexane (1:1.5). A light yellow eluent was obtained, which was evaporated. The residue yellow powder was washed with hexane and dried to give a light yellow microcrystalline powder (27%).