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Papers by Pengxiang Shen
Chemical Science, 2013
A novel rhodium-catalyzed CC bond formation was developed to construct biaryls through unreactive... more A novel rhodium-catalyzed CC bond formation was developed to construct biaryls through unreactive aryl C-S bond cleavage of thioethers with aryl boroxines. This protocol provided a supplemental method of traditional Suzuki-Miyaura coupling. Scheme 1 New strategy to construct biaryl compounds via aryl C-S activation.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 24, 2015
A novel bidentate α-amino oxazolinyl directing group has been developed. Different from previous ... more A novel bidentate α-amino oxazolinyl directing group has been developed. Different from previous directing groups, this newly designed directing group was easily prepared from amino acids and modified in structure. This auxiliary preferentially effects functionalization at secondary C(sp(3) )H bonds, rather than at aryl C(sp(2) )H bonds. The diastereoselectivity of direct arylation between geminal secondary C(sp(3) )H bonds in linear molecules has also been realized for the first time with a chiral directing group by remote chirality relay. Two diastereoisomers are produced with the same chiral source by changing the substituents of substrates and aryl halides.
Organic Letters, 2013
Palladium-catalyzed primary and secondary sp 3 CÀH bond arylation is reported. The method using d... more Palladium-catalyzed primary and secondary sp 3 CÀH bond arylation is reported. The method using diarylhyperiodonium salts as arylation reagents shows good functional group tolerance and proceeds under mild reaction conditions. The KIE experiments show that the CÀH bond activation is the rate-determining step. Transition-metal-catalyzed direct CÀH arylation has emerged as an attractive alternative to traditional synthetic methods. 1 In comparison, most achievements in this field to carry out the formation of CÀC bonds or CÀN bonds are being focused on the activation of sp 2 CÀH bonds of (hetero)arenes. 2 The unreactive sp 3 CÀH activation remains challenging, facing problems that approach both efficiency and selectivity. 3 Some achievements have been made to functionalize the relatively active benzylic and allylic CÀH bonds directly. 4 More recently, many efforts have also been made to perform direct functionalization of the "unreactive" sp 3 CÀH bonds via Pd catalysis. For example, work to achieve Pd-catalzyed "unreactive" sp 3 CÀH arylation was accomplished by using the Nor S-contained directing groups with either aryl halides or organometallic reagents as arylation reagents. 5 Daugulis
Chemical Science, 2013
A novel rhodium-catalyzed CC bond formation was developed to construct biaryls through unreactive... more A novel rhodium-catalyzed CC bond formation was developed to construct biaryls through unreactive aryl C-S bond cleavage of thioethers with aryl boroxines. This protocol provided a supplemental method of traditional Suzuki-Miyaura coupling. Scheme 1 New strategy to construct biaryl compounds via aryl C-S activation.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 24, 2015
A novel bidentate α-amino oxazolinyl directing group has been developed. Different from previous ... more A novel bidentate α-amino oxazolinyl directing group has been developed. Different from previous directing groups, this newly designed directing group was easily prepared from amino acids and modified in structure. This auxiliary preferentially effects functionalization at secondary C(sp(3) )H bonds, rather than at aryl C(sp(2) )H bonds. The diastereoselectivity of direct arylation between geminal secondary C(sp(3) )H bonds in linear molecules has also been realized for the first time with a chiral directing group by remote chirality relay. Two diastereoisomers are produced with the same chiral source by changing the substituents of substrates and aryl halides.
Organic Letters, 2013
Palladium-catalyzed primary and secondary sp 3 CÀH bond arylation is reported. The method using d... more Palladium-catalyzed primary and secondary sp 3 CÀH bond arylation is reported. The method using diarylhyperiodonium salts as arylation reagents shows good functional group tolerance and proceeds under mild reaction conditions. The KIE experiments show that the CÀH bond activation is the rate-determining step. Transition-metal-catalyzed direct CÀH arylation has emerged as an attractive alternative to traditional synthetic methods. 1 In comparison, most achievements in this field to carry out the formation of CÀC bonds or CÀN bonds are being focused on the activation of sp 2 CÀH bonds of (hetero)arenes. 2 The unreactive sp 3 CÀH activation remains challenging, facing problems that approach both efficiency and selectivity. 3 Some achievements have been made to functionalize the relatively active benzylic and allylic CÀH bonds directly. 4 More recently, many efforts have also been made to perform direct functionalization of the "unreactive" sp 3 CÀH bonds via Pd catalysis. For example, work to achieve Pd-catalzyed "unreactive" sp 3 CÀH arylation was accomplished by using the Nor S-contained directing groups with either aryl halides or organometallic reagents as arylation reagents. 5 Daugulis