Diisopropylethylamine → (3R)-3-methyltetrahydro-2H-pyrazino[1,2-a]pyrazine-1,4(3H,6H)-dione

HRID 421229

Reaction equation

HRID 421229 reaction equation
[C:1]([N:8]1[CH2:13][CH2:12][N:11](C(OC(C)(C)C)=O)[CH2:10][CH:9]1[C:21]([OH:23])=O)([O:3]C(C)(C)C)=O.CN(C(O[N:32]1N=N[C:34]2C=CC=C[C:33]1=2)=[N+](C)C)C.[B-](F)(F)(F)F.C(N(C(C)C)CC)(C)C.Cl.COC(=O)[C@@H](C)N>ClCCl.CN(C=O)C>[CH3:34][C@@H:33]1[C:1](=[O:3])[N:8]2[CH2:13][CH2:12][NH:11][CH2:10][CH:9]2[C:21](=[O:23])[NH:32]1

Participants

7

Procedure

To a solution of N,N′-diboc-piperazine-2-carboxylic acid (2 g, 6.06 mmol) in 50 mL of dichloromethane and was added TBTU (2.138 g, 6.66 mmol) and diisopropylethyl amine (1.3 mL, 7.26 mmol). The reaction was stirred for 45 min. In the meantime, a suspension of D-alanine methyl ester hydrochloride (1.249 g, 12.11 mmol) and diisopropylethylamine (3.27 mL, 18.76 mmol) in 20 mL of dichloromethane and 5 mL of DMF was stirred and finally added to the reaction mixture. The reaction was left stirring at room temperature overnight. UPLC-MS analysis showed the expected product (peak at 0.72 min, m/z=416 (M+1), 360 (M−t-Bu+1). The reaction was diluted with dichloromethane and extracted with sat. NaHCO3, dried (Na2SO4), and the solvent removed. The crude (4.242 g) was taken to the next step without further purification.

Workup

  1. stirringwas stirred
  2. additionfinally added to the reaction mixture
  3. waitThe reaction was left
  4. stirringstirring at room temperature overnight

Sources & evidence

ORD record
ord-fe2b0d2769fe4845afe144cd2eb07c41
Source dataset
uspto-grants-2012_01
Patent number
US08097618B2

Linked notes

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