Stereocontrolled construction of condensed .gamma.-lactam ring systems by cationic cyclizations. Rearrangement of a .gamma.-lactam to a .delta.-lactam
摘要:
A new condensation of 3-alkenamides with benzaldehyde in acidic media, notably polyphosphoric acid, leads to gamma-lactam rings with high regio- and stereocontrol. One such gamma-lactam was shown to undergo a novel and stereocontrolled ring-expansion to a delta-lactam.
A Practical and General Amidation Method from Isocyanates Enabled by Flow Technology
作者:Jason D. Williams、William J. Kerr、Stuart G. Leach、David M. Lindsay
DOI:10.1002/anie.201807393
日期:2018.9.10
The addition of carbonnucleophiles to isocyanates represents a conceptually flexible and efficient approach to the preparation of amides. This general synthetic strategy has, however, been relatively underutilized owing to narrow substrate tolerance and the requirement for less favourable reaction conditions. Herein, we disclose a high‐yielding, mass‐efficient, and scalable method with appreciable
Cobalt-electrocatalytic HAT for functionalization of unsaturated C–C bonds
作者:Samer Gnaim、Adriano Bauer、Hai-Jun Zhang、Longrui Chen、Cara Gannett、Christian A. Malapit、David E. Hill、David Vogt、Tianhua Tang、Ryan A. Daley、Wei Hao、Rui Zeng、Mathilde Quertenmont、Wesley D. Beck、Elya Kandahari、Julien C. Vantourout、Pierre-Georges Echeverria、Hector D. Abruna、Donna G. Blackmond、Shelley D. Minteer、Sarah E. Reisman、Matthew S. Sigman、Phil S. Baran
DOI:10.1038/s41586-022-04595-3
日期:2022.5.26
The study and application of transitionmetal hydrides (TMHs) has been an active area of chemical research since the early 1960s1, for energy storage, through the reduction of protons to generate hydrogen2,3, and for organic synthesis, for the functionalization of unsaturated C–C, C–O and C–N bonds4,5. In the former instance, electrochemical means for driving such reactivity has been common place since
Pd-Catalyzed Cross-Coupling of Potassium Alkenyltrifluoroborates with 2-Chloroacetates and 2-Chloroacetamides
作者:Gary A. Molander、Thiago Barcellos、Kaitlin M. Traister
DOI:10.1021/ol401377q
日期:2013.7.5
A protocol for the stereocontrolled synthesis of (E)- and (Z)-beta,gamma-unsaturated esters and amides is reported. 2-Chloroacetates as well as secondary and tertiary 2-chloroacetamides were successfully employed as electrophiles in the Suzuki-Miyaura cross-coupling reaction with potassium (E)- and (Z)-alkenyltrifluoroborates, affording the corresponding products in high yield.
Diastereo- and Regioselectivity in the Reactions of Dilithiated Allylic Secondary Amides with Cyclopent-2-enone
作者:Richard K. Haynes、Scott M. Starling、Simone C. Vonwiller
DOI:10.1021/jo00120a007
日期:1995.7
Stereocontrolled construction of condensed .gamma.-lactam ring systems by cationic cyclizations. Rearrangement of a .gamma.-lactam to a .delta.-lactam
作者:Charles M. Marson、Urszula Grabowska、Timothy Walsgrove、Drake S. Eggleston、Paul W. Baures
DOI:10.1021/jo00081a005
日期:1994.1
A new condensation of 3-alkenamides with benzaldehyde in acidic media, notably polyphosphoric acid, leads to gamma-lactam rings with high regio- and stereocontrol. One such gamma-lactam was shown to undergo a novel and stereocontrolled ring-expansion to a delta-lactam.