Exp148-iii.JPG

Objective

To synthesize a Ugi adduct from phenanthrene-9-carboxaldehyde, 1-heptylamine, tert-butylisocyanide and crotonic acid in methanol using Ugi 4CR following Explan005. This is a repeat of Exp143a.The target compound was ranked 153 in the DEXP014-V1B file from D-EXP014.
Usefulchem Molecule link

[The experiment is repeated because phenanthrene-9-carboxaldehyde which was used in the previous experiment was acquired as a liquid. The aldehyde used here was obtained from Sigma Aldrich as a solid- Mpt-100C]

Procedure

To a one dram vial, charged with methanol (1mL) heptylamine, phenanthrene-9-carboxaldehyde, crotonic acid and tert-butyl isonitrile (0.5mmol each) was added in that order. After each addition, the resulting solution was vortexed for 15 seconds (or more) and confirmed that a homogeneous solution had been obtained. The vial was capped tight and left at room temperature for 3 days. The solution formed solid upon moving it to another spot. The obtained solid was washed with methanol (3 x 500uL), centrifuged each time to obtain a white residue. The wet product was set under a high vac to remove the solvent.
Characterization of 148B: White powder; M.pt~ 179-181C; H-NMR (external image delta.gif ppm, CDCl3) 0.30 (m, 1H), 0.54-0.95 (m, 10H), 1.05-1.2 (m, 1H ), 1.39 (s, 9H), 1.89 (d, 3H J 6.8Hz), 2.86 (bs, 1H), 3.28-3.60 (m 2H ), 5.79 (s,1H), 6.24 (d,1H J 15Hz), 6.87 (s 1H), 7.0-7.15 (m 1H), 7.56-7.76 (m 4H), 7.88 (d 1H J 7.85 Hz), 7.92-8.04 (m 2H), 8.68 (d 1H J 8.25 Hz), 8.73 (d 1H J 8.25Hz); 13C NMR (external image delta.gif ppm, CDCl3) 13.8, 18.2, 22.1, 26.2, 27.9, 28.6, 29.9, 31.0, 45.5, 51.7, 57.8, 122.0, 122.4, 123.1, 124.1, 126.8, 126.9, 127.43, 127.48, 128.9, 129.15, 129.16, 130.3, 130.47, 130.9, 131.0, 142.7, 166.9, 169.9; IR (KBr, 1/cm): v=3315, 3080, 2926, 2855, 1663, 1614, 1452, 1419, 748, 728; HRMS m/z calcd for C31 H40 N2 O2 : 495.298748 [M+Na]; found 495.2997.

ID/ Lib Rank
Solvent
Aldehyde
Amine
Carboxylic Acid
Isocyanide
Ppt Yes/No
148A/153
Methanol
Phenanthrene-9-
carboxaldehyde
n-Heptylamine
Crotonic acid
tert-butylisocyanide
Yes
Quantity
1000uL
0.5mmol, 103.1mg
0.5mmol, 74.1uL
(density=0.777g/ml)
0.5mmol, 43.0mg
0.5mmol, 56.5uL
(density=0.735g/ml)
Yield -118.5mg; 50.1%)
(C31H40N2O2
MW-472.66g/mol)

Results

Phenanthrene-9-Carboxaldehyde (solid from Sigma-Aldrich)
HNMR
n-Heptylamine
HNMR
Crotonic Acid
HNMR
tert-Butyl isocyanide
HNMR

30min after mixing
all components

3 days after mixing
all components

Exp148A-1.JPG
Exp148Asolid.JPG

Characterization of 148B

amount: 118.5 mg
m.p. 179-181C
HNMR(50mg in 700uL CDCl3)
CNMR(50mg in 700uL CDCl3)
HRMS (FAB) [M+Na]
Nominal Mass (FAB) [M+H]
Nominal Mass (FAB) [M+Na]
IR (KBr)

Discussion

The experiment was repeated because Phenanthrene-9-carboxaldhyde which was used in the previous experiment was obtained as a liquid, the HNMR of the liquid does not correspond to the NMR of the compound purchased from Sigma-Aldrich.
To compare the HNMR of 148B with all the starting materials an overlay was created. 148B Vs all starting material Overlay
The multiplet around 3.4 ppm is interesting - can you explain the pattern?
The multiplet between 3.2-3.6 PPM corresponds to the CH2 next to -N (coming from 1-heptyl amine).The pattern (doublet of doublet of doublets) can be explained on the basis of the diasterotopic nature of the protons involved. Each proton on that carbon appears as a distorted doublet of doublet of doublets because of there nonequivalence, resulting in each of them coupling separately with two protons on the next carbon (CH2, also diastereoopic), they also couple to each other (on the same carbon). Therefore the signal is two doublet of doublet of doublet (16 peaks altogether). A simple explanation.

All results are recorded in the Master Table of all Ugi synthesis attempts

Conclusion

A Ugi product was successfully synthesized in 50% yield.

Log

2007-11-20

18:30 Obtained HNMRs of Phenanthrene-9-Carboxaldehyde (Solid from Sigma-Aldrich) and the compound used as "phenanthrene-9-carboxaldehyde" in the previous experiments.
18:45: Obtained HNMR of n-Heptylamine
18:55: Obtained HNMR of Crotonic Acid
20:20 Added methanol (500uL) to a one dram vial, followed by n-heptylamine. The solution was vortexed for 15s.
20:30 Added Phenanthrene-9-carboxaldehyde (0.5mmol, 103.1mg), the solution was vortexed. Even after vortexing for 10min the aldehyde did not disslove in methanol (500uL) Therefore, another 500uL of methanol was added to the solution. The solid now went in to the solution, however a few oil like droplets were observed at the bottom of the vial. The solution homogenized upon standing.
20:50 Added Crotonic Acid (0.5mmol, 43.0mg) and vortexed again, the solution turned completely clear and yellow.
20:55 Added t-butylisocyanide (0.5mmol, 56.5uL) to the above vial, vortexed it for 15s and left it capped tightly in a fume hood.
21:25 Took a picture of the reaction mixture in the vial.

2007-11-23

12:42 The reaction mixture in the vial remained clear (with absolutely no solid in it), when it was checked sitting in the hood.
12:43: Picked-up the vial in order to obtain a picture and placed it in a different spot, however this movement caused an apparent crystal induction, and with in a minute or two the entire solution in the vial turned solid...(awesome!)
12:48 Obtained a picture of the vial containing the solid 148A
15:00 There was no visible solvent remaining in the vial, however it was vortexed for 15s, nothing changed (no solvent still visible)
15:05 Added methanol (500uL), vortexed the vial for 15s, the solvent remained over the solid.
15:10 Sonicated the vial containing undissolved solid and methanol on top for ~1min, then vortexed it for 15s. At this time the solid packing at the bottom of the vial mixed well with the solvent and a pasty mixture covered the walls of the vial.
15:15 The vial was centrifuged (Fisher Scientific Safety 6 Holes Centrifuge) for 1min first, a cloudy supernatant separated from the solid this is when the vial was centrifuged for another 5min (in order to clear-up the supernatant ) .
15:25 A clear supernatant (with few suspended particles) separated out, this was poured out on to a watch glass. To the white residue in the vial more methanol (500uL) was added, it was vortexed for 15s, when a paste was obtained. This was centrifuged again for 5min. The clear supernatant (with few suspended particles) separated out, this was poured out again on to the watch glass.
15:50 For a third time again, to the white residue was added methanol (500uL). The vial was again vortexed (15s), centrifuged (5min).The supernatant (not very clear, this time) was poured out again on to the watch glass. The combined supernatants after, methanol evaporation showed a substantial amount of solid on the watch glass....(to be discarded).
16:15 The vial containing the white solid residue was left in a dessicator connected to a high vac.
17:10 Obtained 118.5mg of the product now called 148B
18:23 Obtained HNMR of 148B (50mg in 700uLCDCl3).
19:21 Obtained CNMR of 148B.

2007-11-25

13:00 Submitted ~5mg of the sample (148B) for MS (FAB) analysis.
19:00 Obtained an IR : Pulverized 148B (~20mg ) with KBr (~200mg) (spectrograde ) using a tiny mortar-pestle, pressed the powder (mix) in to a pellet. Obtained an IR spectrum on a Perkin Elmer FTIR -Model: Spectrum One.

2007-11-29

13:00 Obtained mass spec (FAB) results. (Instrument: VG Analytical VG 70SE High Resolution Mass Spectrometer)

Tags

Phenanthrene-9-carboxaldehydeInChI=1/C15H10O/c16-10-12-9-11-5-1-2-6-13(11)15-8-4-3-7-14(12)15/h1-10H InChIKey: QECIGCMPORCORE-UHFFFAOYAE
tert-butylisocyanideInChI=1/C5H9N/c1-5(2,3)6-4/h1-3H3 InChIKey: FAGLEPBREOXSAC-UHFFFAOYAL
Crotonic Acid: InChI=1/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/f/h5H InChIKey: LDHQCZJRKDOVOX-UHFFFAOYAC
n-Heptylamine : InChI=1/C7H17N/c1-2-3-4-5-6-7-8/h2-8H2,1H3 InChIKey: WJYIASZWHGOTOU-UHFFFAOYAD
targetUgiExp148:InChI=1/C31H40N2O2/c1-6-8-9-10-15-21-33(28(34)16-7-2)29(30(35)32-31(3,4)5)
27-22-23-17-11-12-18-24(23)25-19-13-14-20-26(25)27/h7,11-14,16-20,22,29H,6,8-10,15,21H2,1-5H3,(H,32,35)/b16-7
InChIKey: HOKCUULFCASAQT-FRKPEAEDBY