Synlett 2016; 27(03): 422-426
DOI: 10.1055/s-0035-1560826
letter
© Georg Thieme Verlag Stuttgart · New York

Tandem Aza-Michael and Intramolecular Amidic Ring-Opening Reactions of β-Lactams: A Facile Synthesis of 4-Oxo-4,5-dihydro-1H-pyrroles from β-Lactam Synthons

Priyanka Sharma
a   Department of Applied Sciences, I K Gujral Punjab Technical University, Kapurthala, Punjab 144603, India   Email: gaurav@ptu.ac.in
,
Maninder Jeet Kaur Mann
a   Department of Applied Sciences, I K Gujral Punjab Technical University, Kapurthala, Punjab 144603, India   Email: gaurav@ptu.ac.in
,
Bilash Kuila
a   Department of Applied Sciences, I K Gujral Punjab Technical University, Kapurthala, Punjab 144603, India   Email: gaurav@ptu.ac.in
,
Prabhpreet Singh
b   Department of Chemistry, Guru Nanak Dev University, Amritsar, Punjab 143005, India
,
Gaurav Bhargava*
a   Department of Applied Sciences, I K Gujral Punjab Technical University, Kapurthala, Punjab 144603, India   Email: gaurav@ptu.ac.in
› Author Affiliations
Further Information

Publication History

Received: 26 August 2015

Accepted after revision: 04 October 2015

Publication Date:
13 November 2015 (online)


Abstract

Tandem aza-Michael addition of 3-amino-2-azetidinones with acetylenic esters and subsequent intramolecular amidic ring opening of the initially formed azetidin-3-ylaminoprop- or -but-2-enoic ester is described. The reaction provides a facile route for the formation of functionalized 4-oxo-4,5-dihydro-1H-pyrroles in good yields.

Supporting Information

 
  • References and Notes

    • 1a Chemistry and Biology of β-Lactam Antibiotics. Morin RB, Gorman M. Academic Press; 1982: Vol. 1–3.
    • 1b Southgate R, Branch C, Coulton S, Hunt E In Recent Progress in the Chemical Synthesis of Antibiotics and Related Microbial Products. Vol. 2. Luckacs G. Springer; Berlin: 1993: 621

      For a review on the use of penicillin, see:
    • 3a Nathwani D, Wood MJ. Drugs 1993; 45: 866
    • 3b Holden KG In Chemistry and Biology of β-Lactam Antibiotics. Vol. 2. Morin RB, Gorman M. Academic Press; London: 1982: 114
    • 3c Gootz TD. Clin. Microbiol. Rev. 1990; 13
  • 7 Estevez V, Villacampa M, Menendez JC. Chem. Soc. Rev. 2010; 39: 4402 ; and references cited therein
  • 11 Previous report involving the synthesis of pyrroles using reactions of acyclic trialkyl amines with DMAD, see: Winterfeldt E. Chem. Ber. 1964; 97: 1952
  • 12 For the synthesis of 3-amino-2-azetidinone, see: van der Steen FH, Koten GV. Tetrahedron 1991; 47: 7503 ; and references cited therein
  • 13 General Procedure for the Synthesis of 3 and 4 DMAD (2a; 1.4 mmol) was added to a well-stirred solution of 3-amino-2-azetidinone (1 mmol) in anhydrous solvent (10 mL) at the reaction temperature. The progress of the reaction was monitored by TLC taking the 3-amino-2-azetidinone as the limiting reactant. After completion of reaction, all solvent was removed under reduced pressure. The crude reaction mixture was purified by column chromatography using EtOAc–hexane (20:80) as eluent. The compounds were recrystallized using a mixture of CHCl3 and hexane (20:80) to obtain 3ai and 4ai as pure compounds. For percentage yields and ratios of 3 and 4, see Tables 1 and 2.
  • 14 2-(2-Oxo-1-p-chlorophenyl-4-styryl-azetidin-3-ylamino)-but-2-enedioic Acid Dimethyl Ester (3c) White solid; mp 170–172 °C. 1H NMR (300 MHz, CDCl3): δ = 3.64 (s, 3 H), 3.80 (s, 3 H), 4.94 (dd, J = 5.1, 7.5 Hz, 1 H), 5.431 (s, 1 H), 5.50 (dd, J = 5.1, 8.1 Hz, 1 H), 6.19 (dd, J = 8.1, 15.9 Hz, 1 H), 6.80 (d, J = 15.9 Hz, 1 H), 7.11 (t, J =7.5 Hz, 2 H), 7.25–7.39 (m, 5 H), 7.46 (dd, J = 12.0, 1.2 Hz, 2 H), 8.62 (d, J = 7.0 Hz, 1 H). I3C NMR (75 MHz, CDCl3): δ = 51.1, 52.8, 61.1, 64.4, 92.3, 117.2, 122.1, 124.4, 126.8, 128.3, 128.6, 129.1, 135.80, 136.8, 137.5, 147.7, 163.5, 163.6, 169.8. LRMS: 441.1 [M + 1]. IR (KBr): νmax = 1752.36 (carbonyl of esters), 1736.38 (keto group of lactam), 1515.2, 1390, 1257.13 cm–1. HRMS: m/z calcd for C23H21ClN2O5 [M + H+]: 441.1217; found: 441.1219.
  • 15 4-Oxo-5-(3-phenyl-1-p-tolylamino-allyl)-4,5-dihydro-1H-pyrrole-2,3-dicarboxylic Acid Dimethyl Ester (4b) Pale yellow solid; mp 154–155 °C. 1H NMR (300 MHz, CDCl3): δ = 2.31 (s, 3 H), 3.93 (s, 3 H), 3.97 (s, 3 H), 5.18 (dd, J = 5.4, 8.4 Hz, 1 H), 5.89 (dd, J = 8.4, 15.9 Hz, 1 H), 6.40 (d, J = 5.4 Hz, 1 H), 6.82 (d, J = 15.9 Hz, 1 H), 7.13–7.24 (m, 7 H), 7.41 (d, J = 11.4 Hz, 2 H). I3C NMR (75 MHz, CDCl3): δ = 21.0, 52.8, 53.6, 60.3, 67.0, 117.3, 120.1, 126.8, 128.7, 128.9, 129.7, 130.0, 134.5, 134.8, 134.9, 138.8, 139.9, 157.1, 158.6, 160.0. LRMS 421.2 [M + 1]. IR (KBr): νmax = 1747.24 (carbonyl of esters), 1681.99 (keto group of pyrrole), 1515.2, 1390, 12.57.13 cm–1. HRMS: m/z calcd for C24H25N2O5 [M + H+]: 421.1763; found: 421.1762.