Chemical Papers
extended to the other alkyl alcohols and monoterpenes. An
increase in carbon chain size ꢀavored the conversion oꢀ the
reactions, however, compromised the selectivity oꢀ the ter-
pinyl alkyl ether. The monoterpene structure was also a key
aspect in the etherifcation reaction; the substrate conver-
sion and selectivity ꢀor α-terpinyl methyl ether obeyed the
trends: β-pinene>α-pinene>limonene>camphene. Finally,
the Cs H PW O catalyst was eꢂciently recovered and
da Silva MJ, Liberto NA (2016) Soluble and solid supported Keggin
heteropolyacids as catalysts in reactions ꢀor biodiesel production:
challenges and recent advances. Curr Org Chem 20:1263–1283
da Silva MJ, Teixeira MG (2017) An unexpected behavior oꢀ
H
PMo O heteropolyacid catalyst on the biphasic hydrolysis
3
12 40
oꢀ vegetable oils. RSC Adv 7:8192–8199
da Silva MJ, Silva VWG, Laier LO (2010) Novel H PW O : cata-
3
12 40
lysed esterifcation reactions oꢀ ꢀatty acids at room temperature
ꢀ
or biodiesel production. Catal Lett 135:207–211
2
.5 0.5
12 40
da Silva MJ, Carari DM, da Silva AM (2015) Fe(III)-catalyzed
α-terpinyl derivatives synthesis ꢀrom β-pinene via reactions
with hydrogen peroxide in alcoholic solutions. RSC Adv
reused without loss activity or selectivity. No signifcant
leaching oꢀ the catalyst was verifed.
5
:10529–10536
da Silva MJ, Julio AA, Mosqueira Ayala DA, de Miranda LM (2018)
Fe(SO ) -catalyzed synthesis oꢀ terpenic alcohols esters: a simple
Acknowledgements This study was fnanced in part by the Coorde-
4
3
nação de Aperꢀeiçoamento de Pessoal de Nível Superior—Brasil
and biꢀunctional reusable solid catalyst. Chem Select 3:5742–5748
de Mattos FC, de Carvalho EN, Freitas EF, Paiva MF, Ghesti GF,
Macedo JL, Dias SC, Dias JA (2017) Acidity and characterization
oꢀ 12-tungstophosphoric acid supported on silica-alumina. J Braz
Chem Soc 28:336–347
(
CAPES)—Finance Code 001.
Funding The authors are grateꢀul ꢀor the fnancial support ꢀrom CNPq
and FAPEMIG (Brazil).
de Oliveira AA, da Silva ML, da Silva MJ (2009) Palladium-catalysed
oxidation oꢀ bicycle monoterpenes by hydrogen peroxide in ace-
tonitrile solutions: a metal reoxidant-ꢀree and environmentally
benign oxidative process. Catal Lett 130:424–431
Compliance with ethical standards
Conꢁlict oꢁ interest There are no conꢃicts oꢀ interest to declare.
Dias JA, Caliman E, Dias SC (2004) Eꢁects oꢀ cesium ion exchange
on acidity oꢀ 12-tungstophosphoric acid. Micropor Mesopor Mat
7
6:221–232
Essayem N, Coudurier G, Fournier M, Vedrine J (1995) Acidic and cat-
alytic properties oꢀ Cs H PW O heteropolyacid compounds.
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