KlementineJBS / USYD_PhD_ELN

This repository forms the electronic laboratory notebook (ELN)for Klementine Burrell-Sander's PhD's

2 stars 0 forks source link

KBS45-2 - Nosyl protection of 1,8-diaminooctane #168

Closed KlementineJBS closed 5 months ago

KlementineJBS commented 6 months ago

Link to HIRAC and master page #157

KBS43 - Nosyl protection of linear diamine .docx

Reaction scheme

KBS43 - Nosyl protection of linear amines

Outcome

1.615 g (3.14 mmol, 45%)

KlementineJBS commented 6 months ago

12.12.23

Dissolved SM (1.0007 g, 6.94 mmol) and NEt3 (2.9 mL, 20.8 mmol, 3 equiv.) in THF (40 mL)
Added nosyl chloride (3.6787 g, 16.6 mmol, 2.4 equiv. - some dropped)
Left stirring from ~ 3 pm.
After TLC indicated reaction was not complete, added an additional 1.0453 g of nosyl chloride (4.73 mmol, 0.7 equiv.)
TLC still indicated reaction was not complete at 5.30 pm. Turned off. While SM appears to have been consumed, three spots were clearly evident on TLC - this is thought to be reagent (nosyl chloride), mono-nosylated and bis-nosylated product. Desired product is expected to have the highest Rf.

KlementineJBS commented 6 months ago

14.12.23

Reaction was left untended due to power outage. Quenched with ammonium chloride solution (40 mL), and worked up with chloroform (3 x 50 mL). Washed with brine and dried.

Rotovapped off chloroform and left in fumehood.

KlementineJBS commented 6 months ago

LRMS

KBS45-2 cr.pdf KBS45-2 cr.d.zip

KlementineJBS commented 6 months ago

Purification attempts

Tried to recryst from THF and water. Resulting compound is powdery white solid, not really crystalline. Does seem slightly cleaner by NMR.

KBS45-2 crystal_1.zip

TLC'd to find column conditions. Will likely try a gradient of 10-20% ethyl acetate in hexanes.

KlementineJBS commented 5 months ago

Column conditions

Columned at first in a 0-20% ethyl acetate:hexanes column. Very little came off, so ran a second column from 50-70% which resulted in much higher intensity collections.