KBS25-1 - Propargylation of 1,6-diaminohexane about usyd_phd_eln

[KlementineJBS]

02.11.22

1. Added K2CO3 (1.266 g) to an oven dry flask under nitrogen
2. Added 1,6-diaminohexane (355.4 mg, 3.06 mmol) dissolved in dry MeCN (15 mL)
3. Cooled to 0 C in ice bath
4. Added propargyl bromide (0.6 mL, 6.3 mmol, 2.1 equiv.) dropwise over 1 hour
5. Removed ice bath and left stirring overnight at rt from ~ 3 pm

03.11.22

6. TLC'd at ~10 am in ethyl acetate: pet. benz.

7. Filtered through celite (in a sintered funnel) with DCM to rinse flask
8. Removed DCM by rotary evaporation

LRMS

KBS25-1 RM.d.zip
KBS25-1 RM.pdf

Peaks at 155, 193, 231 suggest mixture of mono, bis and tri-propargylated products ([M+H]). Peak at 231 (tri-propargyl) is largest but this may reflect ease of ionisation.

[KlementineJBS]

07.11.22

Empty vial: 15.7072
Full vial: 16.1965
Mass: 489.3

LCMS/MS

KBS-25-1_1-D_6_1_394.d.zip
KBS-25-1_1-D_6_1_394-_DataAnalysis__Compound_Spectrum_List_Report.pdf
KBS-25-1_1-D_6_1_394_ReportEngine_-Report.pdf

[KlementineJBS]

22.11.22

Began to column crude product (viscous orange liquid). Determined on 20% ethyl acetate in hexanes.

Struggled to dissolve crude product - tried hexane, ethyl acetate/hexane mixture, DCM, chloroform, ether. Was somewhat soluble in chloroform, so put what did dissolve in column and was left with a reddish brown solid remainder (120.6 mg).

F8-11
Empty vial: 15.7919
Full vial: 15.7970
Mass: 5.1 mg

Possibly tris-substituted product.

F18-35
Empty vial: 15.7452
Full vial: 15.9264
Mass: 181.2 mg

Appears to be tetra-substituted product.

[KlementineJBS]

23.11.22

LRMS

KBS25-1 F18-35.d.zip

KBS25-1 F18-35.pdf
269.26 [M+H]+ (tetra substituted compound)

KBS25-1 insoluble.pdf
269.26 [M+H]+ (tetra substituted compound), 231.27 [M+H]+ (tris substituted compound), 191.13 [M+H]+ (bis substituted compound, desired product)

H NMR

KBS25-1 insoluble residue.zip
KBS25-1 18-35_1.zip
KBS25-1 8-11_1.zip

KBS25-1 column fractions.pdf

Supports NMR results - insoluble residue (which dissolved easily in MeOH) is a mixture of the three products, while the main product isolated from the column was the undesired tetra-substituted compound.