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Deposited palladium catalysts for C-C bond forming reactions
Semler, Miloslav ; Štěpnička, Petr (advisor) ; Sedláček, Jan (referee)
Palladium based catalysts are widely used for C-C bonding reactions. This work describes the preparation of several such catalysts deposited onto siliceous, SBA-15 type support and common silica gel, whose surface was modified by organic chains with amine donor groups. The prepared catalysts have been tested in coupling reactions of organotin compounds and organic halides (Stille reactions) under various conditions.
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Phosphinoferrocene amides and hydrazides
Solařová, Hana ; Štěpnička, Petr (advisor) ; Kubíček, Vojtěch (referee)
Title: Phosphinoferrocene amides and hydrazides Author: Hana Solařová Department: Department of Inorganic Chemistry Supervisor: doc. RNDr. Petr Štěpnička, Ph.D. Abstract: While studying functionalized phosphinoferrocene ligands, we recently turned to phosphinoferrocene carboxamides. These donors already proved to be versatile ligands for coordination chemistry and catalysis. This led us to synthesize and study the archetypal representative, 1'-(diphenylphosphino)-1-carbamoylferrocene (5), and the corresponding hydrazide 6. PPh2 COOH Fe Hdpf PPh2 CONH2 Fe 5 PPh2 CONHNH2 Fe 6 This work describes the preparation of primary amide 5 and hydrazide 6 from 1'- (diphenylphosphino)-1-ferrocenecarboxylic acid (Hdpf) via the corresponding acylbenzo- triazole derivative. The hydrazide was alternatively obtained from Hdpf methylester and hydrazine hydrate. Both newly synthesized compounds were characterized by spectroscopic methods (NMR, IR, and MS) and elemental analysis, and their crystal structures were determined by single-crystal X-ray crystallography. The amide was further utilized in the preparation of several palladium complexes, which were characterized in a similar manner including X-ray crystallography. One palladium complex was obtained also from the hydrazide. However, the hydrazide was used mainly as a...
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Preparation of precursors to ferrocenophane ligands
Škoch, Karel ; Štěpnička, Petr (advisor) ; Veselý, Jan (referee)
Title: Preparation of precursors to ferrocenophane ligands Autor. Karel Škoch Department: Department of Inorganic Chemistry (Faculty of Science, Charles University in Prague) Supervisor: doc. RNDr. Petr Štěpnička, Ph.D. This thesis focuses on a comparison of two alternative literature methods for the preparation [3]ferrocenophan-1-one. One-step Friedel-Crafts acylation of ferrocene with acryloylchloride in presence of aluminium chloride doesn't provide satisfactory yields and the product is contamined with inseparable impurities. For the preparation of a larger amount of pure [3]ferrocenophan-1-one is therefore suggested the original three-step synthesis starting from ferrocenecarbaldehyde. Ferrocenecarbaldehyde is first reacted with malonic acid to give β- ferrocenylacrylic acid, which can be easily reduced with hydrogen to β-ferrocenylpropionic acid. Treatment of β-ferrocenylpropionic acid with trifluoracetic anhydride acid induces heteroannular cyclization, affording [3]ferrocenophan-1-one with good purity and yields (up to 70 % over the three steps). All compounds were characterised by spectroscopic methods (1 H NMR, 13 C NMR and IR).
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Immobilised palladium catalysts
Demel, Jan ; Štěpnička, Petr (advisor) ; Vohlídal, Jiří (referee) ; Jirátová, Květa (referee)
Shrnutí V rámci této diplomové práce byl připraven nový komplex [RuCl2(46-1-iso- propvl-4-nrethvlbenzen) { 1'- (dífenvlfosfi no) ferrocenkarboxvlová kvselina-rc P}] a byla stanovena jcho struktura rcntgcnovou difrakcí na monokrystalu. Na tttesoporézltírnolekulové Síto MCM-41 byl zakotvelr kornplex rutltelria dvěuta způsoby.V prvním případě, kdy byla na MCM-41 nejprve zakotvena Hdpf a poté ruthenatý komplex' došlo pravděpodobně k nezávislému zakotvení obou látek. V druhém případě byl ruthenatý konrplex zakotven přímo bez fosfinového linkeru. Tyto molekulový i oba lreterogenni katalyzátory byly použity ke stu- dirt reakce propargylalkoholu s kyselinou benzoovou , za vznikt 2_oxopropvl_ bcnzoátu. oba hctcrogcnní katalyzátory mčlypodobnou aktivitu, cožuka- zuje,že v tottrto případě nezáleželo Ita přítolttttosti fosfinovélro ligandu. Velrrri nízká aktivita heterogenních katalyzátorů v porovnání s homogenním byla způsobena paralelní reakcí propargylalkoholu s křemičitanovým molekulo- vým sítem MCM-41 na neidentifikovaný, pravděpodobně polymerní produkt. Bylo zjištěno, žekatalytická centra se z heterogenních kata|yzátorů vymý- vají, ale v tak malém množství,žerrmožtiu.jíminimálně ještě jedno porržití kataIyzátoru bez výrazné ztráty aktivity'
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