Cyclopentadiene nitroso adducts 1a and ent-1a were synthesised in good yields and good enantiomeric excess from chiral chloro-nitroso derivatives 4 and 5 in the d-mannose and d-ribose series, respectively. The thermal racemisation of these adducts occurred below room temperature. Some other chiral Diels–Alder nitroso adducts were prepared in the d-mandelic, l-prolinol and d-O-methylprolinol series
Accessing nitrosocarbonyl compounds with temporal and spatial control via the photoredox oxidation of N-substituted hydroxylamines
作者:Charles P. Frazier、Leoni I. Palmer、Andrey V. Samoshin、Javier Read de Alaniz
DOI:10.1016/j.tetlet.2015.01.024
日期:2015.6
Photoredox catalysis is employed to generate highly reactive acylnitroso species from hydroxamic acid derivatives. The conditions are shown to be comparable to a previously developed transition metal aerobic oxidation and are amenable to a range of transformations including Diels-Alder and ene reactions. This unique application of such an approach gives access to temporal and spatial control in nitroso chemistry. Published by Elsevier Ltd.
Cyclopropanation of nitroso Diels–Alder cycloadducts and application to the synthesis of a 2′,3′-methano carbocyclic nucleoside
作者:Cheng Ji、Marvin J. Miller
DOI:10.1016/j.tetlet.2010.05.062
日期:2010.7
Treatment of nitroso Diets-Alder cycloadducts 1 with diazomethane in the presence of palladium acetate gives synthetically useful exo-6-oxa-7-azatricyclo[3.2.1.0(2.4)]octane derivatives 7 in good to excellent yield. Using this methodology, a conformationally restricted 2',3'-methano carbocyclic nucleoside was efficiently synthesized from nitroso cycloadduct la in seven steps. (C) 2010 Elsevier Ltd. All rights reserved.
Vanadium-Catalyzed Oxidation of tert-Butyl N-Hydroxycarbamate to tert-Butyl Nitrosoformate and Its Diels–Alder Reaction with Simple and Functionalized Dienes
作者:Yujiro Hoshino、Kenzo Suzuki、Kiyoshi Honda
DOI:10.1055/s-0032-1317148
日期:——
A general and efficient vanadium-catalyzed oxidation of tert-butyl N-hydroxycarbamate to tert-butyl nitrosoformate using alkyl hydroperoxides as terminal oxidants has been developed. The intermediate nitrosocompound was trapped by in situ Diels–Alderreaction with simple and functionalized dienes, providing general access to a variety of functionalized 3,6-dihydro-2H-1,2-oxazines.
A sequence of oxidative cleavage/reductive amination/reductive cleavage enables the preparation of N-substituted cis 5-amino-3-hydroxypiperidines from a readily available bicyclic adduct. This new route provides straightforward and versatile access to drug-relevant scaffolds or fragments.