76529-20-9Relevant academic research and scientific papers
One-Pot C-H Arylation/Lactamization Cascade Reaction of Free Benzylamines
Chand-Thakuri, Pratibha,Landge, Vinod G.,Kapoor, Mohit,Young, Michael C.
supporting information, p. 6626 - 6644 (2020/07/14)
An efficient method has been developed for the synthesis of seven-membered biaryl lactams involving Pd-catalyzed, native amine-directed, ortho-arylation of benzylamines followed by in situ lactamization. This cascade sequence is enabled by the use of 2-iodobenzoates, which facilitates C-H arylation from the free amine under conditions that typically require an improved directing group approach. This reaction is characterized by a broad substrate scope with good functional group tolerance. The need for an ester versus carboxylic acid-functionalized coupling partner is also explored, as is the potential for synthesizing eight-membered biaryl lactams. Various applications are also investigated, including access to the aza-brassinolide core.
Carbon Dioxide-Mediated C(sp2)-H Arylation of Primary and Secondary Benzylamines
Kapoor, Mohit,Chand-Thakuri, Pratibha,Young, Michael C.
supporting information, p. 7980 - 7989 (2019/05/22)
C-C bond formation by transition metal-catalyzed C-H activation has become an important strategy to fabricate new bonds in a rapid fashion. Despite the pharmacological importance of ortho-arylbenzylamines, however, effective ortho-C-C bond formation of free primary and secondary benzylamines using PdII remains an outstanding challenge. Presented herein is a new strategy for constructing ortho-arylated primary and secondary benzylamines mediated by carbon dioxide (CO2). The use of CO2 with Pd is critical to allowing this transformation to proceed under relatively mild conditions, and mechanistic studies indicate that it (CO2) is directly involved in the rate-determining step. Furthermore, the milder temperatures furnish free amine products that can be directly used or elaborated without the need for deprotection. In cases where diarylation is possible, an interesting chelate effect is shown to facilitate selective monoarylation.
Reactions of Et3ZnLi with ketones: Electronic and steric effects
Musser,Richey Jr.
, p. 7750 - 7756 (2007/10/03)
Toluene solutions of composition Et3ZnLi react rapidly with aldehydes and ketones to form addition products. Et3ZnNa and Et3ZnK solutions react readily with the same substrates although metalation, as well as addition, is significant with substrates having α-hydrogens. The Et3ZnM solutions react with 2-cyclohexenone to give mainly the 1,4-addition product. Relative rates of addition of Et3ZnLi to substituted acetophenones give a Hammett ρ of 2.78. Addition of Et3ZnLi to acetophenone is slowed significantly by α and ortho methyl substituents; relative rates of addition to acetophenone, o-methylacetophenone, and tert-butyl phenyl ketone are 1.00, 0.012, and 0.003.
