1120-95-2, 3-Chloropyridazine is a pyridazine compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated
Ethyl (cis)-2-oxo-1-oxa-3-azaspiro[4.5]decane-8-carboxylate and ethyl (trans)-2-oxo-1-oxa-3-azaspiro[4.5]decane-8-carboxylate mixture (85/15 mixture) (obtained from combination of four different batches prepared in a similar fashion to preparation of Intermediates 2 and 3, procedures a and b, 10 g, 44.0 mmol), K3PO4 (28.0 g, 132 mmol), copper(I) iodide (0.838 g, 4.40 mmol), 3-chloropyridazine (prepared according to WO/0107416, 6.05 g, 52.8 mmol) were collected into a 250 ml reaction flask, deareated, and then suspended in 1,4-dioxane (150 ml) under nitrogen. Trans-1,2-diaminocyclohexane (1.058 ml, 8.80 mmol) was added to the resulting mixture. The reaction was then warmed up to reflux (ext temp. 130 C., int temp 105 C.). The reaction mixture was stirred at that temperature for overall 24 hours. The reaction mixture was taken up with DCM (1000 ml) and poured into water (300 ml) containing 10 ml of ammonium hydroxide, and left under stirring for 10 min. Then, the resulting organic phase was washed with water (2¡Á100 ml) and brine (2¡Á100 ml), dried over Na2SO4, filtered and then concentrated. The resulting crude was purified with Biotage SP1, over 65i silica column, using cyclohexane and EtOAc as eluent to afford two different batches of the title compound.Batch 1: Ethyl (trans)-2-oxo-3-(3-pyridazinyl)-1-oxa-3-azaspiro[4.5]decane-8-carboxylate (3.4 g) was isolated as a single isomer, colourless solid, contaminated by ca 30% of starting chloropyridazine. This batch left at room temperature, in the light, after some days, resulted in a strongly dark coloured and degradated residue.Batch 2: A 80/20 mixture of trans/cis isomers was isolated as a colourless solid (2.2 g) and repurified on Biotage SP1, with a Biotage 65i silica column, using cyclohexane and ethyl acetate as eluent to give isomerically pure ethyl (trans)-2-oxo-3-(3-pyridazinyl)-1-oxa-3-azaspiro[4.5]decane-8-carboxylate (1.6 g)1H NMR (400 MHz, CDCl3): delta 8.96 (dd, 1H), 8.56 (dd, 1H), 7.50 (dd, 1H), 4.20 (s, 2H), 4.18 (q, 2H), 2.51 (quint, 1H), 2.17-1.75 (m, 8H), 1.29 (t, 3H); UPLC-MS: 0.60 min, 306 [M+H]+.From these two purifications two batches of cis isomer were also isolated:Batch 1: ethyl (cis)-2-oxo-3-(3-pyridazinyl)-1-oxa-3-azaspiro[4.5]decane-8-carboxylate as single isomer and colourless solid (4.7 g)Batch 2: ethyl (cis)-2-oxo-3-(3-pyridazinyl)-1-oxa-3-azaspiro[4.5]decane-8-carboxylate (0.5 g).1H NMR (400 MHz, CDCl3): delta 8.96 (dd, 1H), 8.57 (dd, 1H), 7.50 (dd, 1H), 4.18 (q, 3H), 4.14 (s, 2H), 2.51 (quint, 1H), 2.46-2.37 (m, 1H), 2.21-1.66 (m, 8H), 1.29 (t, 3H); UPLC-MS: 1.04 min, 306 [M+H]+.
1120-95-2, As the paragraph descriping shows that 1120-95-2 is playing an increasingly important role.
Reference£º
Patent; Biagetti, Matteo; Contini, Stefania Anna; Genski, Thorsten; Guery, Sebastien; Leslie, Colin Philip; Mazzali, Angelica; Pizzi, Domenica Antonia; Sabbatini, Fabio Maria; Seri, Catia; US2009/203705; (2009); A1;,
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