217795-77-2Relevant academic research and scientific papers
Hydromethylation of Unactivated Olefins
Dao, Hai T.,Li, Chao,Michaudel, Quentin,Maxwell, Brad D.,Baran, Phil S.
supporting information, p. 8046 - 8049 (2015/07/15)
A solution to the classic unsolved problem of olefin hydromethylation is presented. This highly chemoselective method can tolerate labile and reactive chemical functionalities and uses a simple set of reagents. An array of olefins, including mono-, di-, and trisubstituted olefins, are all smoothly hydromethylated. This mild protocol can be used to simplify the synthesis of a specific target or to directly "edit" complex natural products and other advanced materials. The method is also amenable to the simple installation of radioactive and stable labeled methyl groups.
New Synthetic Approach to Cyclopenta-Fused Heterocycles Based upon a Mild Nazarov Reaction
Occhiato, Ernesto G.,Prandi, Cristina,Ferrali, Alessandro,Guarna, Antonio,Venturello, Paolo
, p. 9728 - 9741 (2007/10/03)
The Pd-catalyzed coupling reaction of lactam or lactone-derived vinyl triflates and phosphates with α-alkoxydienylboronates gives conjugated alkoxytrienes in which one of the double bonds is embedded in a heterocyclic moiety. If subjected to mild acidic hydrolysis, these compounds undergo a 4π electrocyclization process (Nazarov reaction) which furnishes cyclopenta-fused O- and N-heterocycles in good yields. The scope of the work has been that of closely examining the role and effect of both the heteroatom and the heterocycle ring size on the outcome of the electrocyclization, as well as the torquoselectivity of this process. The presence of the heteroatom was essential in stabilizing the oxyallyl cation intermediate, thus allowing the reaction to occur. The ring size was also a basic parameter in the cyclization step: five-membered azacycles required more drastic conditions to give 5-5 fused systems and did so only after an initial hydrolysis to the corresponding divinyl ketones. As for the torquoselectivity, with both 2-methyl and 4-methyl substituted lactam derivatives steric interactions seem to have a role in forcing the conrotatory process to take place in one sense only: allowing the synthesis of diastereomerically pure compounds to be realized. Because different patterns of substitution on the heterocycle are compatible with the reaction conditions, the methodology developed could be very useful for the synthesis of natural products and biologically active compounds containing cyclopenta-fused O- and N-heterocycle moieties.
Biohydroxylations of Cbz-protected alkyl substituted piperidines by Beauveria bassiana ATCC 7159
Aitken, Suzanne J.,Grogan, Gideon,Chow, Cathy S.-Y.,Turner, Nicholas J.,Flitsch, Sabine L.
, p. 3365 - 3370 (2007/10/03)
N-Benzyloxycarbonyl (Cbz) protected piperidines are hydroxylated with greater regioselectivity than the corresponding N-benzoyl analogues when incubated with the fungus Beauveria bassiana ATCC 7159. Cbz-protected piperidines 1-3, 5-7, have been biotransfo
