Efficient Synthesis of Branched Polyamine Based Thermally Stable Heterogeneous Catalyst for Knoevenagel Condensation at Room Temperature

Functionalized alkenes were successfully synthesized via a clean procedure in a short time by using a new recycled heterogeneous catalyst prepared from Moroccan oil shale, this catalyst is characterized by different technics such XRD, BET-BJH, MEB-EDS, and TGA, before it’s has been used in the Knoevenagel condensation between different aldehydes and active methylenes. The results showed that coupling the catalyst with ultrasound irradiations could improve the catalytic system in this transformation by achieving the products in a very short time, the results showed clearly that this catalyst could be considered as excellent recyclable support in Knoevenagel condensation.

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Efficient synthesis of pyrido[2,3-d]pyrimidine-7-carboxylic acids catalyzed by a TiO2/SiO2 nanocomposite in aqueous media at room temperature

Zeitschrift für Naturforschung B ◽

10.1515/znb-2018-0076 ◽

2018 ◽

Vol 73 (9) ◽

pp. 641-645 ◽

Cited By ~ 1

Author(s):

Sepehr Sadegh-Samiei ◽

Shahrzad Abdolmohammadi

Keyword(s):

Heterogeneous Catalyst ◽

Carboxylic Acids ◽

Room Temperature ◽

Aqueous Media ◽

Reaction Times ◽

Molar Ratio ◽

Efficient Synthesis ◽

Reaction Conditions ◽

Moderate Reaction ◽

Recyclable Heterogeneous Catalyst

AbstractA novel and efficient synthesis of eight 5-aryl-1,3-dimethyl-2,4-dioxo-1,2,3,4,5,8-hexahydropyrido[2,3-d]pyrimidine-7-carboxylic acids using a TiO2/SiO2 nanocomposite with a molar ratio of 1:1 as a recyclable heterogeneous catalyst is described. The desired products, five of which are new, are formed in short reaction times (2–3 h) with high to excellent yields (94%–98%) under very moderate reaction conditions (room temperature, aqueous media).

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Investigation of the V4+-Centre in 6H- and 4H-SIC by the Method of Spectral-Hole Burning

MRS Proceedings ◽

10.1557/proc-512-369 ◽

1998 ◽

Vol 512 ◽

Author(s):

C. Hecht ◽

R. Kummer ◽

A. Winnacker

Keyword(s):

Electronic Properties ◽

Room Temperature ◽

Hole Burning ◽

Band Offset ◽

Spectral Hole Burning ◽

Type Ii ◽

Thermally Stable ◽

Spectral Hole

ABSTRACTIn the context of spectral-hole burning experiments in 4H- and 6H-SiC doped with vanadium the energy positions of the V4+/5+ level in both polytypes were determined in order to resolve discrepancies in literature. From these numbers the band offset of 6H/4H-SiC is calculated by using the Langer-Heinrich rule, and found to be of staggered type II. Furthermore the experiments show that thermally stable electronic traps exist in both polytypes at room temperature and considerably above, which may result in longtime transient shifts of electronic properties.

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Efficient Synthesis of Tetrahydrobenzo[b]pyrans under Solvent‐Free Conditions at Room Temperature

Synthetic Communications ◽

10.1080/00397910600640230 ◽

2006 ◽

Vol 36 (16) ◽

pp. 2363-2369 ◽

Cited By ~ 36

Author(s):

Liangce Rong ◽

Xiaoyue Li ◽

Haiying Wang ◽

Daqing Shi ◽

Shujiang Tu ◽

...

Keyword(s):

Room Temperature ◽

Solvent Free ◽

Efficient Synthesis ◽

Solvent Free Conditions

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Aqueous, One-Pot, Three-Component Reaction for Efficient Synthesis of 2-[4-(Arylsulfonyl)piperazin-1-yl]-1,3-benzothiazole, ‑1H-benzimidazole, or -1,3-benzoxazole Derivatives

Synlett ◽

10.1055/s-0036-1590972 ◽

2017 ◽

Vol 28 (17) ◽

pp. 2295-2298

Author(s):

Kommula Dileep ◽

M. Murty

Keyword(s):

Room Temperature ◽

Efficient Synthesis ◽

One Pot ◽

Three Component Reaction ◽

Aqueous Conditions

A simple and efficient synthetic protocol has been developed involving a one-pot three-component reaction of a 2-chlorobenzazole, piperazine, and an arenesulfonyl chloride under aqueous conditions at room temperature in the absence of a catalyst, ligand, or base. By using this protocol, a variety of 2-[4-(arylsulfonyl)piperazin-1-yl]-1,3-benzothiazole, -1H-benzimidazole, and -1,3-benzoxazole derivatives were synthesized in excellent yields.

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