Boron tribromide → HCID 86662218, compound

Temperature

-78 °C

A solution of 17a (0.050 g, 0.177 mmol) in dry CH2Cl2 (15 mL) in a flame-dried single-neck flask was cooled to −78° C., and 0.55 mL of a 1.0 M solution of BBr3 in CH2Cl2 were added dropwise to the flask. The reaction was stirred at −78° C. for 2 h and then at room temperature for 2 h. The reaction was returned to the dry ice/acetone bath and carefully quenched by the addition of 3 mL anhydrous MeOH. The quenched reaction was evaporated to dryness, taking care to keep the water bath below 40° C. The solid residue was redissolved in MeOH, and evaporated again, repeating this process a total of four times. The resulting tan solid was dried under high vacuum overnight and then crystallized from MeOH-Et2O to yield a fine, white powder (0.043 g, 0.144 mmol, 81.1%); mp>250° C. 1H NMR: (500 MHz, DMSO): δ 9.08 (s, 1H, ArOH); 8.47 (m, 1H, NH2); 8.34 (m, 1H, NH2); 8.19 (s, 1H, ArOH); 6.60 (d, 1H, J=8.0 Hz, ArH); 6.43 (d, 1H, J=8.0 Hz, ArH); 3.18-3.06 (m, 2H, ArCHCH2NH2CH2); 2.99-2.88 (m, 3H, ArCHCH2NH2CH2); 2.79 (dd, 1H, J=3.5, 17.5 Hz, ArCH2); 2.45-2.33 (m, 1H, ArCH2); 2.04-1.87 (m, 3H, ArCH2CH2CHCH2); 1.71 (bd, 1H, J=16.0 Hz, ArCH2CH2CHCH2); 1.58-1.52 (m, 1H, ArCH2CH2). ESIMS (M+H)=220.

1. waitat room temperature for 2 h
2. customcarefully quenched by the addition of 3 mL anhydrous MeOH
3. customThe quenched reaction
4. customwas evaporated to dryness
5. customthe water bath below 40° C
6. dissolutionThe solid residue was redissolved in MeOH
7. customevaporated again
8. customThe resulting tan solid was dried under high vacuum overnight
9. customcrystallized from MeOH-Et2O

ORD record

ord-733a08646825466fa5b9e1998c1f850f

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09359303B2