Diisopropylamine → HCID 21278093, compound

HRID 2291960Notes

Reaction equation

HRID 2291960 reaction equation
C([Li])CCC.C(NC(C)C)(C)C.[Si:13]([N:20]1[CH:23]([S:24][C:25]([C:38]2[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=2)([C:32]2[CH:37]=[CH:36][CH:35]=[CH:34][CH:33]=2)[C:26]2[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=2)[CH2:22][C:21]1=[O:44])([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14].[CH:45]([C:47]1[CH:48]=[N:49][N:50]([CH3:52])[CH:51]=1)=[O:46].[Cl-].[NH4+].N1CCC1=O.C(NCC)C>C1COCC1.C(Cl)(Cl)Cl>[Si:13]([N:20]1[CH:23]([S:24][C:25]([C:38]2[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=2)([C:32]2[CH:37]=[CH:36][CH:35]=[CH:34][CH:33]=2)[C:26]2[CH:27]=[CH:28][CH:29]=[CH:30][CH:31]=2)[CH:22]([CH:45]([OH:46])[C:47]2[CH:48]=[N:49][N:50]([CH3:52])[CH:51]=2)[C:21]1=[O:44])([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14]

Participants

10

Reactant 7

HCID 7912DiisopropylamineHCID 8021Diethylamine3×HCID 25517Ammonium ChlorideHCID 1367212-Azetidinone2×HCID 5731171-Methyl-1H-pyrazole-4-carbaldehydeHCID 129287451-t-Butyldimethylsilyl-4-tritylthio-2-azetidinoneHCID 178418339Butyllithium

Product 1

HCID 21278093HCID 21278093, compound

Reagents, catalysts & solvents 2

HCID 6212ChloroformSolvent2×HCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
-30 °C

Procedure

A solution of n-butyl lithium (1.06M. in hexane, 1.13 ml) was added to a solution of diisopropylamine (0.17 ml) in dry THF (8 ml) at -30° C. under dry argon. After stirring at -30° C. for 10 minutes the mixture was cooled to -76° C. and treated with a solution of 1-t-butyldimethylsilyl-4-tritylthioazetidin-2-one (1) (459 mg) in dr THF (4 ml). After a further 15 minutes at -76° C. the stirred mixture was treated with a solution of 4-formyl-1-methylpyrazole (132 mg) (I. L. Finar and G. H. Lord, J. Chem. Soc. 1957, 3314) in dry THF (1 ml). After 20 minutes at -76° C. the stirred mixture was treated with saturated ammonium chloride solution (5 ml) and worked up as for Preparation 1(a) to give two fractions. The less polar fraction contained a trans-isomer (Isomer A) of the title azetidinone (12) (165 mg), an amorphous solid, νmax (CHCl3) 3600-3100, 1735 cm-1 ; δppm (CDCl3) 0.92 (9H, s), 1.1-1.8 (1H, br. signal, exch. D2O), 3.32 (1H, dd, J2 and 2 Hz), 3.50 (1H, d, J2 Hz), 3.76 (3H, s), 4.46 (1H, d, J2 Hz), 7.10-7.60 (17H, m), the Me2Si signals were obscured by the TMS signal. [Found (diethylamine chemical ionisation): MH+, 570 and M+Et2NH]+, 643]. The more polar fraction contained the other trans-isomer (Isomer B) of the title azetidinone (12) (185 mg), an amorphous solid, νmax (CHCl3) 3600-3100, 1735 cm-1 ; δppm (CDCl3) 0.80 (9H, s), 1.7-2.5 (1H, br. signal, exch. D2O), 3.59 (1H, dd, J6 and 2 Hz), 3.70 (3H, s), 3.87 (2H, 2d, J2 Hz and J6 Hz), 6.91 (1H, s), 7.10-7.50 (16H, m), the Me2Si signals were obscured by the TMS signal. [Found (diethylamine chemical ionisation): MH+, 570].

Workup

  1. temperaturewas cooled to -76° C.
  2. customto give two fractions

Sources & evidence

ORD record
ord-2169bed1bcba45c8818b7730eda06792
Source dataset
uspto-grants-1989_01
Patent number
US04798828

Reaction notes

Loading…