Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 61-70-1, name is 1-Methylindolin-2-one, A new synthetic method of this compound is introduced below., HPLC of Formula: C9H9NO
General procedure: Isatin (0.1 mol, 14.7 g) was dissolved in DMF (60 mL) and finely ground anhydrous K2CO3 (0.15 mol,20.7 g) was added under stirring. RX (0.15 mol) was added dropwise and mixture was heated at 60-70C for 3 h (as alkylation reagent RX were used Me2SO4, EtI, n-PrBr, AmBr, BnCl, PMBCl,respectively). After cooling to room temperature mixture was poured into ice water (200 mL).Precipitated orange solid was filtereted, washed with water and recrystallized from ethanol (95%) togive N-alkylated isatins as red crystalls in 37-92% yield. The purity of obtained compounds weredetermined by melting points, which corresponded to those published in the literature (ref. 2-4).N-Substituted isatin (10 mmol) was mixed with 16 M N2H4¡¤H2O (15 mL). The suspension was heatedat reflux 3 h (caution: rapid gas evolution), then it was cooled to room temperature, diluted with waterS4(40 mL) and extracted with EtOAc (3 x 25 mL). Organic phase was washed with water (25 mL), brine (25 mL), then it was dried over Na2SO4 and evaporated under reduced pressure to give the desired product. The latter was recrystallized from hexane and small amount of EtOAc to give N-substituted indolin-2-one as yellow solid in 47-96% yield. The purity of obtained compounds were determined by melting points and 1H NMR spectra data, which corresponded to those published in the literature (ref. 5,6).N-Substituted indolin-2-one (2 mmol) were dissolved in dry DMF (5 mL) and NaH (60% dispersion in mineral oil, 6 mmol, 240 mg) was portionwise added carefully at a temperature of -15 C. When the rapid evolution of H2 stops, the mixture allowed to stir for 10 min. Then solution of 1,2-dibromoethane (508 mg, 2.7 mmol) in dry DMF (3 mL) was added to the mixture. The latter was warmed to room temperature and stirred overnight. Then it was cooled with ice, diluted with water (20 mL) and extracted with PhMe (2 x 15 mL). Organic phase was washed with water (2 x 15 mL), brine (15 mL) and then it was dried over Na2SO4. Evaporation under reduced pressure gave the desired product. The latter was washed with hexane to remove mineral oil or purified by flash column chromatography (eluent: hexane/CH2Cl2). The spiro[cyclopropane-1,3′-indolin]-2′-ones 1 are yellow solids, except N-amyl substituted spiro[cyclopropane-1,3′-indolin]-2′-one, which is brown liquid. The purity of obtained compounds were determined by 1H NMR spectra data. Corresponding cyclopropanes were previously known in the literature (ref. 7-11).
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Article; Buev, Evgeny M.; Moshkin, Vladimir S.; Sosnovskikh, Vyacheslav Y.; Tetrahedron Letters; vol. 59; 37; (2018); p. 3409 – 3412;,
Indoline – Wikipedia,
Indoline | C8H9N – PubChem