%0 Journal Article
%T Carboxylation of Aromatics by CO<sub>2</sub> under ˇ°Si/Al Based Frustrated Lewis Pairsˇ±  Catalytic System
%A Miaofei Gu
%A Zhenmin Cheng
%J Journal of Materials Science and Chemical Engineering
%P 103-108
%@ 2327-6053
%D 2015
%I Scientific Research Publishing
%R 10.4236/msce.2015.31015
%X <p class=\"MsoNormal\">
	<span lang=\"EN-US\">Carboxylation of aromatics by CO<sub>2</sub> to
generate corresponding carboxylic acids is recently providing a novel approach
to utilize the green gas CO<sub>2</sub>, in which the activation of CO<sub>2</sub> is the key procedure.
Among the many catalytic systems employed in the carboxylation, the concept of
ˇ°Frustrated Lewis Pairsˇ± (FLPs) was scarcely mentioned, which perform
excellently in activating small molecules like CO<sub>2</sub>. The FLPs are combinations
of Lewis acids and Lewis bases which failed to form adducts due to their bulky
steric congestion. In this paper, we first attempted various Si/Al Based FLPs
to catalyze the carboxylation of aromatics through the activation of CO<sub>2</sub>, and a
good yield of 62% - 97% was obtained. The reaction mechanism was proposed, involving
the activation of CO2 mainly contributed by AlCl<st1:chmetcnv unitname=\"in\" sourcevalue=\"3\" hasspace=\"True\" negative=\"False\" numbertype=\"1\" tcsc=\"0\" w:st=\"on\"><sub>3</sub> in</st1:chmetcnv> cooperation with organosilane, forming an intermediate
consisting of CO<sub>2</sub>, AlCl<sub>3</sub>, and R<sub>4</sub>Si, as well as the subsequent electrophilic
attack to aromatics, thus to promote the carboxylation reaction.</span>
</p>
%K Carboxylation
%K Frustrated Lewis Pairs
%K Carbon Dioxide
%K Aromatic
%K Catalytic System
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=55576