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An efficient and green approach for the synthesis of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates using Bi₂O₃/ZrO₂ as a reusable catalyst.

ABSTRACT: A novel material of bismuth loaded on zirconia (Bi₂O₃/ZrO₂) is synthesized by simple wet-impregnation method and characterized by several techniques (P-XRD, TEM, SEM, BET, etc.). Bi₂O₃/ZrO₂ proved to be a good catalyst for the four-component, one-pot reaction to produce a new series of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylate derivatives with excellent yields (91 to 98%) under mild conditions at RT with short reaction times (≈20 min). The structures of the target molecules were confirmed by ¹H NMR, ¹³C NMR, ¹⁵N NMR, HRMS and FT-IR. The catalyst is easily separable and can be reused for six cycles without ostensible loss of activity. This method is inexpensive, atom-efficient and no chromatographic separations are needed.

SUBMITTER: Bhaskaruni SVHS

PROVIDER: S-EPMC9080279 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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An efficient and green approach for the synthesis of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates using Bi2O3/ZrO2 as a reusable catalyst.

Bhaskaruni Sandeep V H S SVHS Maddila Suresh S van Zyl Werner E WE Jonnalagadda Sreekantha B SB

RSC advances 20180401 29

A novel material of bismuth loaded on zirconia (Bi2O3/ZrO2) is synthesized by simple wet-impregnation method and characterized by several techniques (P-XRD, TEM, SEM, BET, etc.). Bi2O3/ZrO2 proved to be a good catalyst for the four-component, one-pot reaction to produce a new series of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylate derivatives with excellent yields (91 to 98%) under mild conditions at RT with short r ...[more]

PMID: 35542231

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