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Synteza estrów kwasu fosfonooctowego i ich praktyczne zastosowanie w otrzymywaniu fosforylowanych kumaryn

Frynas Sławomir, Szwaczko Katarzyna, Dziuba Kamil

Przemysł Chemiczny

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2023

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T. 102, nr 1

73--76

PL

Estry kwasu fosfonooctowego 1 (R¹ = R² = Me, Et, i-Pr, R³ = Et, i-Pr, PhCH₂, Ph) otrzymano w reakcji Michaelisa i Arbuzowa fosforynów alkilowych z estrami kwasu bromoctowego. Reakcje przeprowadzono bez rozpuszczalnika w temp. 80-110°C. Otrzymane estry 1 użyto następnie w reakcji z aldehydem salicylowym w obecności katalizatora (pirolidyna i MeCOOH), uzyskując fosforylowane kumaryny 2 (R = Me, Et, i-Pr) z prawie całkowitą konwersją i wysokimi wydajnościami wydzielonego produktu, wynoszącymi 75-85%.

EN

Phosphonoacetic acid esters 1 (R¹ = R² = Me, Et, i-Pr, R³ = Et, i-Pr, PhCH₂, Ph) were obtained via Michaelis-Arbuzov reaction of alkyl phosphites with bromoacetates, carried out without solvent at 80-110°C. Treatment of 1 with salicylaldehyde in the presence of a catalyst (pyrrolidine and acetic acid) gave phosphorylated coumarins 2 (R = Me, Et, i-Pr) with almost complete conversion and high isolated yields up to 75-85%.

2

Hydrothermal synthesis of zeolites from green container glass

Maisuria Jenika, Elmes Victoria K., Hurt Andrew P., Coleman Aimee A., Coleman Nichola J.

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 5

784--796

EN

Landfilling and stockpiling unrecycled colored container glass represents a considerable failure in sustainability with respect to the conservation of energy and mineral resources. In this study, the single-step hydrothermal synthesis of low-silica zeolites from a mixture of waste green container glass and aluminum foil (Al:Si = 1) in 4 M NaOH(aq) at 125 °C was followed at 1, 3, 7 and 14 days. The principal phases, sodalite and cancrinite, appeared within 1 day accompanied by minor quantities of hydrogarnet and tobermorite arising from a stoichiometric excess of calcium ions in the parent glass. Products of 63, 67, 71 and 72% crystallinity were obtained at 1, 3, 7 and 14 days, respectively, with partial successive conversion of sodalite to cancrinite over time. Ion-exchange and catalytic applications of sodalite and cancrinite arise from the high anionic charge of the 1:1 ratio of alternating SiO44- and AlO45units within their aluminosilicate frameworks. In this respect, the uptake capacity of the 14-day zeolitic product for Cu2+ and Cd2+ ions (1.58 meq g-1 and 1.66 meq g-1, respectively) was within the expected range for zeolites and compared favorably with those reported for other inorganic sorbents derived from industrial and municipal wastes. The 14-day product was also found to be an effective basic heterogeneous catalyst for the Knoevenagel condensation reaction.

3

Synteza estru dietylowego kwasu 3,4-bis(4-metoksyfenylo)-1H-pirolo-2,5-dikarboksylowego, półproduktu w syntezie alkaloidów z grupy Polycitone, Lamellarin i Storniamide

Buszta Natalia

Chemical Technology & Biotechnology

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2017

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Vol. 1

17--22

PL

Opisano syntezę symetrycznie podstawionej pochodnej pirolu, użytecznego produktu pośredniego w syntezie znanych alkaloidów i ich analogów pochodzenia morskiego. Substratem jest aldehyd anyżowy, który w sześciu etapach, z wykorzystaniem m. in.: kondensacji Knoevenagela, uwodornienia alifatycznego wiązania podwójnego i kluczowej pośredniej utleniającej dimeryzacji 2-azydo-3-(4-metoksyfenylo)propionianu etylu chlorkiem tytanu (IV), pozwala na otrzymanie tytułowej pochodnej.

EN

Synthesis of a new building block of symmetrically substituted pyrrole derivative, which is useful intermediate in the synthesis of known alkaloids and their marine analogues, is described. The substrate is anisaldehyde, which in six steps with the use of Knoevenagel condensation, hydrogenation of the aliphatic double bond and the key titanium (IV)-mediated oxidative dimerization of 2-azidocarboxylic ester allows to obtain the title derivative.

4

Kinetics aspects of the knoevenagel condensation - the influence of microwaves irradiation

Bednarz S., Bogdal D.

Polish Journal of Chemical Technology

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2003

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Vol. 5, nr 3

10-11

EN

The mechanism of the Knoevenagel condensation has been studied. The research were focused on the influence of microwave irradiation on the reaction yield. Rate enhancement of the investigated reaction under microwave condition was observed.