33530-84-6Relevant academic research and scientific papers
Allylic oxidation of steroidal olefins by vanadyl acetylacetonate and tert-butyl hydroperoxide
Grainger, Wendell S.,Parish, Edward J.
, p. 103 - 109 (2015)
Abstract Readily available vanadyl acetylacetonate was found to oxidize the allylic sites of Δ5 steroidal alcohols without protection of hydroxyl groups. Cholesterol, dehydroepiandrosterone, cholesterol benzoate, cholesterol acetate, pregnenolone, and 5-pregnen-3,20-diene were oxidized to 7-keto products using vanadyl acetylacetonate in one pot reactions at room temperature in the presence of oxygen and water.
Laccase-mediated oxyfunctionalization of 3β-hydroxy-Δ5-steroids
Khomutov, Sergey M.,Shutov, Andrey A.,Chernikh, Alexey M.,Myasoedova, Nina M.,Golovleva, Ludmila A.,Donova, Marina V.
, p. 47 - 52 (2016)
Laccase mediator systems (LMS) were studied as catalysts for steroid oxidation. The fungal laccases from Lentinus strigosus 1566 and Trametes versicolor were used in the work. Among five mediators screened, 1-hydroxybenzotriasol (HBT) excelled in activity. The LMS effectively catalyzed oxidation of 3β-hydroxy-Δ5-steroids like DHEA (3β-hydroxyandrost-5-en-17-one) and pregnenolone (3β-hydroxypregn-5-en-20-one), while no activity was observed towards 3-oxo-4-ene-steroids (androstenedione, 9α-hydroxyandrostenedione, testosterone and 20-hydroxymethylpregn-4-en-3-one). The pathway of DHEA oxidation by LMS included the hydroxylation at positions 7α and 7β followed by oxidation of the corresponding 7(α/β)-alcohols to form 3β-hydroxyandrost-5-ene-7,17-dione. Regiospecific oxidation of allylic hydroxyl functions by LMS was confirmed using 3β,7α- and 3β,7β-dihydroxyandrost-5-en-17-ones as substrates. 3β-Hydroxypregn-5-ene-7,20-dione was produced with LMS as an only product from pregnenolone. The yield of crystalline product reached 58.3% yield with a purity of 96%. The results demonstrate that application of LMS may be a promising approach for steroid oxyfunctionalization.
Visible-Light-Enabled Allylic C-H Oxidation: Metal-free Photocatalytic Generation of Enones
Liu, Chao,Liu, Hui,Zheng, Xuan,Chen, Shanyi,Lai, Qihong,Zheng, Changlong,Huang, Mingqiang,Cai, Kaicong,Cai, Zhixiong,Cai, Shunyou
, p. 1375 - 1381 (2022/02/07)
A practical and efficient method has been established for the direct oxidation of allylic C-H bonds catalyzed by visible-light-enabled photoredox agents. This protocol uses oxygen as the sole oxidant under metal-free conditions at room temperature and pro
Metal-Free Allylic Oxidation of Steroids Using TBAI/TBHP Organocatalytic Protocol
Lam, Ying-Pong,Yeung, Ying-Yeung
supporting information, p. 2369 - 2372 (2018/04/19)
A mild, efficient and organocatalytic allylic oxidation of steroids using a TBAI/TBHP protocol has been developed. A range of bioactive Δ5-en-7-ones can be easily prepared from the corresponding Δ5-steroids. The methodology features several advantages, including readily available starting materials, environmentally benign oxidant, high functional group compatibility, and metal-free catalysis.
N-Hydroxyphthalimide catalyzed allylic oxidation of steroids with t-butyl hydroperoxide
Zhao, Qian,Qian, Chao,Chen, Xin-Zhi
, p. 1 - 6 (2015/02/19)
A new and optimized procedure for the allylic oxidation of Δ5-steroids with t-butyl hydroperoxide in the presence of catalytic amounts of N-hydroxyphthalimide (NHPI) under mild conditions was developed, showing excellent regioselectivity and chemoselectivity (functional group compatibility). It was found that Co(OAc)2 could enhance the catalytic ability of NHPI resulting in better yields and shorter reaction times. The reaction mechanism and the scope of the reaction with a variety of Δ5-steroidal substrates were also investigated.
An effective method for allylic oxidation of Δ5-steroids using tert-butyl hydroperoxide
Li, Yuancheng,Wu, Xianghong,Lee, Tae Bum,Isbell, Eleanor K.,Parish, Edward J.,Gorden, Anne E. V.
experimental part, p. 1807 - 1810 (2010/05/17)
"Chemical equation presented" An allylic oxidation method for Δ5-steroids using TBHP as oxidant with a 2-quinoxalinol salen Cu(II) complex as catalyst is reported. A variety of Δ5- steroidal substrates are selectively oxidized to the corresponding enones. Excellent yields are achieved (up to 99% under optimized conditions) while significantly reducing reaction times required as compared to other current methods.
Optimal TBHP allylic oxidation of Δ5 - Steroids catalyzed by dirhodium caprolactamate
Choi, Hojae,Doyle, Michael P.
, p. 5349 - 5352 (2008/09/17)
Dirhodium caprolactamate is the most efficient catalyst for the oxidation of Δ5-steroids to 7-keto-Δ5-steroids by 70% tert-butyl hydroperoxide in water (T-HYDRO). Isolated product yields range from 38 to 87%.
