Pyridine → HCID 58234690, compound

To a solution of salicylaldehyde (10.39 g, 85.08 mmol) and pyridine (7.57 mL, 1.1 eq.) in dichloromethane (40 mL) in a 250 mL round-bottom flask was added a solution of 1M isopropyl chloroformate in toluene (93.60 mL, 1.1 eq.) slowly in 20 minutes to maintain the internal temperature below −25° C. using a cold bath of dry ice/acetone. White precipitate began to form during the addition and more precipitate was seen after the addition was complete. The mixture was removed from the cold bath and stirred for 2 hours with the application of a slow increase of temperature. Subsequently, the reaction mixture was evaporated to half the volume on a rotary evaporator, diluted with ethyl acetate (50 mL), washed with ice cold water (2×100 mL), 1N NaOH (3×50 mL), ice water (2×50 mL) and cold brine (1×100 mL), dried over anhydrous MgSO4 and evaporated on a rotary evaporator to produce 15.85 g (88%) of yellow oil. The carbonate (10.52 g) was distilled in high vacuum to yield 9.32 g of colorless oil (b.p. 101-103° C./0.8 torr). 1H NMR (300 MHz, CDCl3): δ 10.22 (s, 1H), 7.92 (dd, J=2.1, 7.5 Hz, 1H), 7.68 (dt, J=2.1, 7.5 Hz, 1H),7.47 (t, J=7.5 Hz, 1H), 7.32 (d, J=7.5 Hz, 1H), 5.04 (m, 1H), 1.45 (d, J=6.3 Hz, 6H).

1. temperatureto maintain the internal temperature below −25° C.
2. customto form during the addition and more precipitate
3. additionafter the addition
4. customThe mixture was removed from the cold bath
5. temperaturea slow increase of temperature
6. customSubsequently, the reaction mixture was evaporated to half the volume
7. customon a rotary evaporator
8. additiondiluted with ethyl acetate (50 mL)
9. washwashed with ice cold water (2×100 mL), 1N NaOH (3×50 mL), ice water (2×50 mL) and cold brine (1×100 mL)
10. dry with materialdried over anhydrous MgSO4
11. customevaporated on a rotary evaporator

ORD record

ord-d21dee7f8ca749458ad413c1af518c0b

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08314081B2