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Ring Expansions of β-Lactams and β-(thio)lactones

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Synthesis of 4- to 7-membered Heterocycles by Ring Expansion

Part of the book series: Topics in Heterocyclic Chemistry ((TOPICS,volume 41))

Abstract

The skeleton of β-lactams and β-lactones is present in biologically active compounds. For example, the β-lactam ring is present in classical antibiotics such as penicillins and cephalosporins. On the other hand, there are several natural products containing a β-lactone moiety, with interesting inhibitory activity. In addition, both fragments are very useful synthetic intermediates for the preparation of cyclic and acyclic compounds. The ring strain present in both motifs is involved in this versatile reactivity. This chapter is devoted to the synthesis of five- to seven-membered heterocycles by ring expansion of β-lactams and β-lactones. Different methodologies have been described, and the mechanism for the formation of the products has been discussed. In addition, the applicability of some of the processes has been demonstrated by the synthesis of fragments of natural or biologically relevant compounds. The contributions presented in this chapter have been selected mainly from the developments achieved in the last decade.

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Abbreviations

Bn:

Benzyl

Boc:

t-Butoxycarbonyl

DBU:

1,8-Diazabicyclo[5.4.0]undec-7-ene

DCE:

1,1-Dichloroethane

DIAD:

Diisopropyl azodicarboxylate

DIBAL:

Diisobutylaluminium hydride

DIPEA:

Diisopropylethylamine

DMAP:

4-Dimethylaminopyridine

DMSO:

Dimethyl sulfoxide

dpm:

Dipivaloylmethanato

EDA:

Ethyl diazoacetate

EDG:

Electron donating group

EDTA:

Ethylenediaminetetraacetic acid

EWG:

Electron withdrawing group

FMOC:

9-Fluorenylmethoxycarbonyl

HMDS:

Hexamethyldisilazide

Ipy2BF4 :

Bis(pyridine)iodonium tetrafluoroborate

LDA:

Lithium diisopropylamide

Lys:

Lysine

NBS:

N-Bromosuccinimide

NIS:

N-Iodosuccinimide

Orn:

Ornithine

p-ABSA:

4-Acetamidobenzenesulfonyl azide

PMB:

p-Methoxybenzyl

PMP:

p-Methoxyphenyl

PPY:

4-Pyrrolidinopyridine

PTSA:

p-Toluenesulfonic acid

TBAF:

Tetra n-butylammonium fluoride

TBCA:

Tribromoisocyanuric acid

TF:

Trifluoromethanesulfonyl

TFA:

Trifluoroacetic acid

TMS:

Trimethylsilyl

Tph:

2-Thiophenyl

Ts:

p-Toluenesulfonyl

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Authors and Affiliations

  1. Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain

    Benito Alcaide & Cristina Aragoncillo

  2. Instituto de Química Orgánica General, IQOG-CSIC, Juan de la Cierva 3, 28006, Madrid, Spain

    Pedro Almendros

Authors
  1. Benito Alcaide
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  2. Pedro Almendros
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  3. Cristina Aragoncillo
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Corresponding authors

Correspondence to Benito Alcaide , Pedro Almendros or Cristina Aragoncillo .

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Editors and Affiliations

  1. Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering Ghent University, Ghent, Belgium

    Matthias D’hooghe

  2. Department of Chemistry, Hankuk University of Foreign Studies, Yongin-si, Korea (Republic of)

    Hyun-Joon Ha

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Alcaide, B., Almendros, P., Aragoncillo, C. (2015). Ring Expansions of β-Lactams and β-(thio)lactones. In: D’hooghe, M., Ha, HJ. (eds) Synthesis of 4- to 7-membered Heterocycles by Ring Expansion. Topics in Heterocyclic Chemistry, vol 41. Springer, Cham. https://doi.org/10.1007/7081_2015_153

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