Water → HCID 88536339, compound

4c (9.00 g, 11.3 mmol) was dissolved in THF (50 mL), forming a colourless solution, in a 250 mL RB flask. A tip of a microspatula measure of MEHQ was then added to this solution. A 125 mL pressure-equalising addition funnel was connected to this flask and the funnel connected in turn to a nitrogen-vacuum manifold. Separately trifluoroacetic acid (50 mL) and water (17 mL) were mixed together and then placed in the addition funnel and the apparatus was then flushed with nitrogen. The reaction flask was then surrounded with an ice-water cooling bath and the 4c/THF solution cooled to ≦+5 deg C. The TFA/H2O solution was then added dropwise to the reaction mixture over a period of 1 hour at ≦+5 deg C. The reaction mixture was then allowed to warm slowly to room temperature under nitrogen. This reaction mixture was then stirred at room temperature under a nitrogen atmosphere for a period of 18 hours. The solution contained a small amount of floccular material (polymer) and was filtered in order to remove it. The filtrate and was then stripped to dryness in vacuo using a rotary evaporator yielding several grams of a viscous dark yellow oil which was further dried at higher vacuum (oil immersion pump) for a period of 1 hour at room temperature. This oil was taken up in CH2Cl2 (100 mL) and extracted with 2×150 mL portions of saturated aqueous NaHCO3 solution and a single 150 mL portion of de-ionised water. The organic layer was then partitioned and separated before being dried over anhydrous MgSO4 for a period of 45 minutes. The drying mixture was then filtered and the collected solid washed with 2×25 mL portions of CH2Cl2. The filtrate and washings were combined and then stripped to dryness in vacuo using a rotary evaporator to yield a pale yellow viscous oil which was further dried in vacuo (oil immersion pump) at room temperature forming a pale yellow “foam”. After 7 hours of drying in vacuo at room temperature the “foam” was broken up with a spatula to yield a pale yellow light powder. Yield: 7.4 g (91%). 1H NMR (d6-DMSO, spectrum acquired at 100° C. to reduce spectral complexity caused by conformation stereoisomerism) δ 1.00 (bs, 4H, hexamethylene bridge —CH2—), 1.44 (bs, 4H, hexamethylene bridge —CH2—), 2.99 (t, 2H, hexamethylene bridge >NCH2—), 3.07 (t, 2H, hexamethylene bridge >NCH2—), 3.88 (s, 2H, >NCH2C(═O)), 4.27 (m, 4H, 2× fluorenyl (Ar)2CH— and ArstyrylCH2N<), 4.48 (d, 2H, Fmoc OCH2—), 4.55 (d, 2H, Fmoc OCH2—), 5.23 (d, 1H, ═C—H), 5.75 (d, 1H, ═C—H), 6.72 (dd, 1H, ═C—H), 7.06 (d, 2H, ArH), 7.35 (m, 10H, ArH), 7.60 (m, 4H, ArH), 7.83 (d, 4H, ArH), 9.37 (s, 1H, —CH(═O)).

1. customforming a colourless solution
2. additionA 125 mL pressure-equalising addition funnel
3. customwas connected to this flask
4. customthe apparatus was then flushed with nitrogen
5. customThe reaction flask was then surrounded with an ice-water cooling bath
6. temperaturethe 4c/THF solution cooled to ≦+5 deg C
7. additionThe TFA/H2O solution was then added dropwise to the reaction mixture over a period of 1 hour at ≦+5 deg C
8. filtrationwas filtered in order
9. customto remove it
10. customa rotary evaporator

ORD record

ord-4c8da96d21a34b458a8eb11922e7ee91

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09115063B2