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KlementineJBS / USYD_PhD_ELN

This repository forms the electronic laboratory notebook (ELN)for Klementine Burrell-Sander's PhD's
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KBS45-1 - Nosyl protection of 1,8-diaminooctane #163

Closed KlementineJBS closed 9 months ago

KlementineJBS commented 10 months ago

Link to HIRAC and master page #157

KBS43 - Nosyl protection of linear diamine .docx

Rationale

Nosyl is an electron deficient PG and will help to stabilise the N- required during the alkylation reaction. Alternatiavely, a nosyl-protected amine could participate in the Fukuyama-Mitsunobu reaction.

Reaction scheme

KBS43 - Nosyl protection of linear amines

Outcome

818.3 mg (1.59 mmol, 88%)

KlementineJBS commented 10 months ago

5.12.23

  1. added 1,8-diaminooctane (260.4 mg, 1.81 mmol) and nosyl chloride (960.6 mg, 4.34 mmol, 2.4 equiv.) to a flask and dissolved in chloroform (6 mL)
  2. Added NEt3 (0.8 mL, 5.42 mmol, 3 equiv.)
  3. Left stirring for ~ 20 minutes at rt

Reaction swiftly turned white with precipitate.

TLC with 1:9:90 NH4OH:MeOH:DCM indicated completion.

Quenched with ammonium chloride solution, then worked up with DCM (25 mL) then chloroform (2 x 25 mL) - should have been chloroform all the way through. Washed with water and brine. Reaction yielded a relatively large amount of fluffy white solid - was concerned that some of it was ammonium chloride but it didn't seem soluble in water at all.

A solvent screen revealed that the solid was only really soluble in DMF at rt.

KlementineJBS commented 9 months ago

LRMS

KBS43-3 cr.pdf KBS43-3 cr.d.zip

KlementineJBS commented 9 months ago

H NMR

Appears to be product.

KBS43-3 cr.pdf KBS43-3 cr DMSO_1.zip KBS43-3 cr_1.zip

KlementineJBS commented 9 months ago

Vial: 15.3726 Mass: 818.3 mg (1.59 mmol, 88%)

KlementineJBS commented 9 months ago

Considerably higher yield suggests that part of the issue previously was one of the reagents.