35519-42-7Relevant articles and documents
Fe-Catalyzed Anaerobic Mukaiyama-Type Hydration of Alkenes using Nitroarenes
Bhunia, Anup,Bergander, Klaus,Daniliuc, Constantin Gabriel,Studer, Armido
supporting information, p. 8313 - 8320 (2021/03/08)
Hydration of alkenes using first row transition metals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama-type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe-catalyzed anaerobic Markovnikov-selective hydration of alkenes using nitroarenes as oxygenation reagents is reported. The nitro moiety is not well explored in radical chemistry and nitroarenes are known to suppress free radical processes. Our findings show the potential of cheap nitroarenes as oxygen donors in radical transformations. Secondary and tertiary alcohols were prepared with excellent Markovnikov-selectivity. The method features large functional group tolerance and is also applicable for late-stage chemical functionalization. The anaerobic protocol outperforms existing hydration methodology in terms of reaction efficiency and selectivity.
Studies on the Oxidation of cis- and trans-Pinane with Molecular Oxygen
Brose, Thomas,Pritzkow, Wilhelm,Thomas, Gerda
, p. 403 - 409 (2007/10/02)
The pinanes are preferably attacked at the tertiary C-H bond in 2-position, but products of the oxidative attack at the secondary C-H-bonds in 3- and 4-position are also found.At 100 deg C cis-pinane is attacked more easily than trans-pinane (kcis : ktrans = 6.4), the relative rates of attack at the secondary C-H bonds in positions 3 and 4 with respect to the tertiary C-H bond in 2-position were also determined (in cis-pinane ksec : ktert = 0.027; in trans-pinane ksec : ktert = 0.20).After the attack at the 2-C-H bond the radical formed can either react with oxygen to form the corresponding cis- and trans-peroxy radicals and further to give cis- and trans-2-hydroperoxy pinane or fragmentate to the monocyclic radical derived from α-terpinene, giving as a final products α-terpinene hydroperoxide and the bicyclic 8-hydroperoxy 4,4,8-trimethyl 2,3-dioxabicyclononane.The corresponding alcohols were found after reduction with sodium sulphite.The oxidation at position 2 of the pinanes delivers not only the cis- and trans-hydroperoxide but also, as short-lived intermediates, the corresponding 2-pinanyloxy radicals.These radicals fragmentate forming a carbon radical with cyclobutane structure whose oxidation products were identified.Besides fragmentation of the 2-pinanyloxy radical also an intramolecular H-transfer from the methyl group in 9-position to the oxygen of the trans-pinanyloxy radical takes place leading to 9-hydroperoxy trans-pinane-2-ol.
Rearrangement of Pinane Derivatives. Part 8. Deamination of 2αH-Pinan-3α-ylamine
Giddings, Rodney M.,Jones-Parry, Richard,Salmon, J. Roger,Whittaker, David
, p. 725 - 728 (2007/10/02)
Solvolysis of 2αH-pinan-3α-yl toluene-p-sulphonate has been shown to proceed with concomitant 1,2-hydride shift to give the pinan-2-yl carbocation.Contrary to earlier reports, this species reacts normally to give, in good yield, pinan-2-yl substitution products.In contrast the pinan-3-ylamines react via a similar route, but give much smaller amounts of pinan-2-yl products.The usual reasons for differences between solvolysis and deamination (i.e. the intermediacy of diazonium ions and/or high-energy ions) can be discounted, and possible reasons for the differences in behaviour are discussed.