Výsledky vyhledávání - "Stanlei I. Klein"

Akademický článek

Dehydration of d-fructose to 5-hydroxymethyl-2-furfural in DMSO using a hydrophilic sulfonated silica catalyst in a process promoted by microwave irradiation

Autor: Sandro L. Barbosa, Milton de S. Freitas, Wallans T. P. dos Santos, David Lee Nelson, Stanlei I. Klein, Giuliano Cesar Clososki, Franco J. Caires, Adriano C. M. Baroni, Alexandre P. Wentz

Publikováno v: Scientific Reports, Vol 11, Iss 1, Pp 1-5 (2021)

Abstract SiO2-SO3H, with a surface area of 115 m2/g, pore volumes of 0.38 cm3g−1 and 1.32 mmol H+/g, was used as a 10% w/w catalyst for the preparation of 5-hydroxymethyl-2-furfural (HMF) from fructose. A conversion of 100% was achieved in a microw

Externí odkaz: https://doaj.org/article/3094e9a0a95f4ea386d5545fc64d58cd

Zobrazit plný text záznamu

Plný text ve formátu HTML

Akademický článek

Tandem Transesterification–Esterification Reactions Using a Hydrophilic Sulfonated Silica Catalyst for the Synthesis of Wintergreen Oil from Acetylsalicylic Acid Promoted by Microwave Irradiation

Autor: Sandro L. Barbosa, David Lee Nelson, Milton de S. Freitas, Wallans Torres Pio dos Santos, Stanlei I. Klein, Giuliano C. Clososki, Franco J. Caires, Alexandre P. Wentz

Publikováno v: Molecules, Vol 27, Iss 15, p 4767 (2022)

SiO2–SO3H, with a surface area of 115 m2/g and pore volume of 0.38 cm3g−1, and 1.32 mmol H+/g was used as a 20% w/w catalyst for the preparation of methyl salicylate (wintergreen oil or MS) from acetylsalicylic acid (ASA). A 94% conversion was ac

Externí odkaz: https://doaj.org/article/2fe4f21285db4cbd86a650f080532293

Zobrazit plný text záznamu

Akademický článek

Catalytic Transformation of Triglycerides to Biodiesel with SiO2-SO3H and Quaternary Ammonium Salts in Toluene or DMSO

Autor: Sandro L. Barbosa, Adeline C. Pereira Rocha, David Lee Nelson, Milton S. de Freitas, Antônio A. P. Fulgêncio Mestre, Stanlei I. Klein, Giuliano C. Clososki, Franco J. Caires, Danilo L. Flumignan, Letícia Karen dos Santos, Alexandre P. Wentz, Vânya M. Duarte Pasa, Regiane D. Fernandes Rios

Publikováno v: Molecules, Vol 27, Iss 3, p 953 (2022)

SiO2-SO3H, with a surface area of 115 m2·g−1, pore volumes of 0.38 cm3·g−1 and 1.32 mmol H+/g, was used as a transesterification catalyst. Triglycerides of waste cooking oil reacted with methanol in refluxing toluene to yield mixtures of diglyc

Externí odkaz: https://doaj.org/article/f1a62fedb370465bb7230a6495c8aad8

Zobrazit plný text záznamu

Plný text ve formátu HTML

Akademický článek

The preparation of benzyl esters using stoichiometric niobium (V) chloride versus niobium grafted SiO2 catalyst: A comparison study

Autor: Sandro L. Barbosa, Camila D. Lima, Melina A.R. Almeida, Larissa S. Mourão, Myrlene Ottone, David L. Nelson, Stanlei I. Klein, Lucas D. Zanatta, Giuliano C. Clososki, Franco J. Caires, Eduardo J. Nassar, Gabriela R. Hurtado

Publikováno v: Heliyon, Vol 4, Iss 3, Pp e00571- (2018)

Two solvent free methods of a one-to-one alcohol/acid mol ratio synthesis of benzyl esters of the formic, acetic, benzoic, salicylic, nicotinic, and oxalic acids are described. The stoichiometric reactions used 1.5 mol ratio solid NbCl5 as the reagen

Externí odkaz: https://doaj.org/article/26f47beac59e4b0dbfcbd48ea6e6ddb3

Zobrazit plný text záznamu

Akademický článek

Efeitos estéricos e eletrônicos de substituintes alquilas em catalisadores titanocênicos solúveis na polimerização sindioespecífica de estireno

Autor: Brasilio C. A. Pereira, Stanlei I. Klein, Marcos L. Dias

Publikováno v: Polímeros, Vol 9, Iss 4, Pp 110-115 (1999)

Titanocenos são catalisadores solúveis conhecidos para a polimerisação estereoespecífica de olefinas pró-quirais como o estireno. Nesse trabalho descrevemos as relações entre as características do poliestireno e a estrutura do precursor do c

Externí odkaz: https://doaj.org/article/9261865114a442dda77af034551b57e0

Zobrazit plný text záznamu

Synthesis and variable temperature 31P NMR spectra of the cobalt, rhodium and iridium complexes [M(P(O)(OMe)2)(P(OMe)3)4] (M = Co, Rh, Ir)

Autor: Stanlei I. Klein, John F. Nixon

Publikováno v: Journal of Organometallic Chemistry. 302:87-99

Syntheses of [M(P(O)(OMe)2)(P(OMe)3)4] (M = Co, Rh, Ir) and variable temperature 31P NMR studies are described, and mechanistic implications discussed.

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::1899cc743ace4aa0ed7835de7b0a6eb2
https://doi.org/10.1016/0022-328x(86)80064-x

Zobrazit plný text záznamu

Vyhledávací nástroje:

Upřesnit hledání