Выдержка
A domino synthesis of dispiro-fused N-vinyl beta-lactams from diazo-Meldrum's acid and 2H-azirines or 5-alkoxyisoxazoles via the "2-azabuta-1,3-diene formation/Staudinger ketene-imine cycloaddition" sequence is described. The Rh-2(Piv)(4)-catalyzed formation of the 2-azabuta-1,3-diene intermediates in the first stage of the reaction sequence proceeds via addition of the rhodium carbenoid to the azirines/isoxazoles and provides the first example of the generation of iminium-type ylides from diazo-Meldrum's acid. This methodology was extended to monospiro-beta-lactams, which were synthesized in two steps using acyclic alpha-diazocarbonyl compounds in the stage of the formation of 2-azabuta-1,3-dienes. The method allows for the rapid assemblage of the carbon part of the azetidin-2-one system from diazo compounds only and affords spiro- and dispiro-beta-lactams in moderate yields. A bromine atom in the 2-bromoalkenyl moiety of the synthesized beta-lactams can be easily substituted by hydrogen under catalytic hydrogenation conditions or by 2-pyridyl-substituent via the Stille cross-coupling reaction.
Язык оригинала | Английский |
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Страницы (с-по) | 6821-6830 |
Число страниц | 10 |
Журнал | Organic and Biomolecular Chemistry |
Том | 17 |
Номер выпуска | 28 |
DOI | |
Состояние | Опубликовано - 28 июл 2019 |
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[2+1+1] Assembly of spiro beta-lactams by Rh(ii)-catalyzed reaction of diazocarbonyl compounds with azirines/isoxazoles. / Golubev, Artem A.; Smetanin, Ilia A.; Agafonova, Anastasiya; Rostovskii, Nikolai; Khlebnikov, Alexander F.; Starova, Galina L.; Novikov, Mikhail S.
В: Organic and Biomolecular Chemistry, Том 17, № 28, 28.07.2019, стр. 6821-6830.Результат исследований: Научные публикации в периодических изданиях › статья
TY - JOUR
T1 - [2+1+1] Assembly of spiro beta-lactams by Rh(ii)-catalyzed reaction of diazocarbonyl compounds with azirines/isoxazoles
AU - Golubev, Artem A.
AU - Smetanin, Ilia A.
AU - Agafonova, Anastasiya
AU - Rostovskii, Nikolai
AU - Khlebnikov, Alexander F.
AU - Starova, Galina L.
AU - Novikov, Mikhail S.
PY - 2019/7/28
Y1 - 2019/7/28
N2 - A domino synthesis of dispiro-fused N-vinyl beta-lactams from diazo-Meldrum's acid and 2H-azirines or 5-alkoxyisoxazoles via the "2-azabuta-1,3-diene formation/Staudinger ketene-imine cycloaddition" sequence is described. The Rh-2(Piv)(4)-catalyzed formation of the 2-azabuta-1,3-diene intermediates in the first stage of the reaction sequence proceeds via addition of the rhodium carbenoid to the azirines/isoxazoles and provides the first example of the generation of iminium-type ylides from diazo-Meldrum's acid. This methodology was extended to monospiro-beta-lactams, which were synthesized in two steps using acyclic alpha-diazocarbonyl compounds in the stage of the formation of 2-azabuta-1,3-dienes. The method allows for the rapid assemblage of the carbon part of the azetidin-2-one system from diazo compounds only and affords spiro- and dispiro-beta-lactams in moderate yields. A bromine atom in the 2-bromoalkenyl moiety of the synthesized beta-lactams can be easily substituted by hydrogen under catalytic hydrogenation conditions or by 2-pyridyl-substituent via the Stille cross-coupling reaction.
AB - A domino synthesis of dispiro-fused N-vinyl beta-lactams from diazo-Meldrum's acid and 2H-azirines or 5-alkoxyisoxazoles via the "2-azabuta-1,3-diene formation/Staudinger ketene-imine cycloaddition" sequence is described. The Rh-2(Piv)(4)-catalyzed formation of the 2-azabuta-1,3-diene intermediates in the first stage of the reaction sequence proceeds via addition of the rhodium carbenoid to the azirines/isoxazoles and provides the first example of the generation of iminium-type ylides from diazo-Meldrum's acid. This methodology was extended to monospiro-beta-lactams, which were synthesized in two steps using acyclic alpha-diazocarbonyl compounds in the stage of the formation of 2-azabuta-1,3-dienes. The method allows for the rapid assemblage of the carbon part of the azetidin-2-one system from diazo compounds only and affords spiro- and dispiro-beta-lactams in moderate yields. A bromine atom in the 2-bromoalkenyl moiety of the synthesized beta-lactams can be easily substituted by hydrogen under catalytic hydrogenation conditions or by 2-pyridyl-substituent via the Stille cross-coupling reaction.
KW - CARBENOID FUNCTIONALIZATION
KW - RHODIUM CARBENOIDS
KW - CYCLOADDITION REACTION
KW - DIAZO-COMPOUNDS
KW - KETENES
KW - IMINES
KW - ESTERS
KW - DIAZOKETONES
KW - INSERTION
KW - COPPER
U2 - 10.1039/c9ob01301f
DO - 10.1039/c9ob01301f
M3 - статья
VL - 17
SP - 6821
EP - 6830
JO - Organic and Biomolecular Chemistry
JF - Organic and Biomolecular Chemistry
SN - 1477-0520
IS - 28
ER -