62717-50-4Relevant articles and documents
Synthesis and dopamine receptor pharmacological evaluations on ring C ortho halogenated 1-phenylbenzazepines
Alberts, Ian,Giri, Rajan,Harding, Wayne W.,Namballa, Hari K.,Sarker, Ananta
, (2020)
A series of 1-phenylbenzazepines containing bromine or chlorine substituents at the ortho position of the appended phenyl ring (2′-monosubstituted or 2′,6′- disubstituted patterns) were synthesized and evaluated for affinity towards dopamine D1
A new clade of styrene monooxygenases for (R)-selective epoxidation
Xiao, Hu,Dong, Shuang,Liu, Yan,Pei, Xiao-Qiong,Lin, Hui,Wu, Zhong-Liu
, p. 2195 - 2201 (2021/04/12)
Styrene monooxygenases (SMOs) are excellent enzymes for the production of (S)-enantiopure epoxides, but so far, only one (R)-selective SMO has been identified with a narrow substrate spectrum. Mining the NCBI non-redundant protein sequences returned a new distinct clade of (R)-selective SMOs. Among them,SeStyA fromStreptomyces exfoliatus,AaStyA fromAmycolatopsis albispora, andPbStyA fromPseudonocardiaceaewere carefully characterized and found to convert a spectrum of styrene analogues into the corresponding (R)-epoxides with up to >99% ee. Moreover, site 46 (AaStyA numbering) was identified as a critical residue that affects the enantioselectivity of SMOs. Phenylalanine at site 46 was required for the (R)-selective SMO to endow excellent enantioselectivity. The identification of new (R)-selective SMOs would add a valuable green alternative to the synthetic tool box for the synthesis of enantiopure (R)-epoxides.
Aerobic epoxidation of styrene over Zr-based metal-organic framework encapsulated transition metal substituted phosphomolybdic acid
Hu, Dianwen,Song, Xiaojing,Zhang, Hao,Chang, Xinyu,Zhao, Chen,Jia, Mingjun
, (2021/04/19)
Catalytic epoxidation of styrene with molecular oxygen is regarded as an eco-friendly alternative to producing industrially important chemical of styrene oxide (STO). Recent efforts have been focused on developing highly active and stable heterogeneous catalysts with high STO selectivity for the aerobic epoxidation of styrene. Herein, a series of transition metal monosubstituted heteropolyacid compounds (TM-HPAs), such as Fe, Co, Ni or Cu-monosubstituted HPA, were encapsulated in UiO-66 frameworks (denoted as TM-HPA@UiO-66) by direct solvothermal method, and their catalytic properties were investigated for the aerobic epoxidation of styrene with aldehydes as co-reductants. Among them, Co-HPA@UiO-66 showed relatively high catalytic activity, stability and epoxidation selectivity at very mild conditions (313 K, ambient pressure), that can achieve 82 % selectivity to STO under a styrene conversion of 96 % with air as oxidant and pivalaldehyde (PIA) as co-reductant. In addition, the hybrid composite catalyst can also efficiently catalyze the aerobic epoxidation of a variety of styrene derivatives. The monosubstituted Co atoms in Co-HPA@UiO-66 are the main active sites for the aerobic epoxidation of styrene with O2/PIA, which can efficiently converting styrene to the corresponding epoxide through the activation of the in-situ generated acylperoxy radical intermediate.
