2- Amino-3-picoline rhodium

Optimized reaction conditions call for the use of Wilkinson s catalyst in conjunction with the organocatalyst 2-amino-3-picoline (60) and a Br0nsted add. Jun and coworkers have demonstrated the effectiveness of this catalyst mixture for a number of reactions induding hydroacylation and C—H bond fundionalization [25]. Whereas, in most cases, the Lewis basic pyridyl nitrogen of the cocatalyst ads to dired the insertion of rhodium into a bond of interest, in this case the opposite is true - the pyridyl nitrogen direds the attack of cocatalyst onto an organorhodium spedes (Scheme 9.11). Hydroamination of the vinylidene complex 61 by 3-amino-2-picoline gives the chelated amino-carbene complex 62, which is in equilibrium with a-bound hydrido-rhodium tautomers 63 and 64. 

This two-step synthesis of ketones has been improved from the aldehyde into one-step synthesis with the cocatalyst system of the rhodium complex and 2-amino-3-picoline, which reacts with an aldehyde to give an aldimine in situ. The ketimine produced is easily converted to a ketone by in situ hydrolysis with H20, which is formed in the step of condensation of the aldehyde with the amine (Eq.56) [125]. 

Related Reagents. Bis(bicyclo[2.2.1]hepta-2,5-diene)rho-dium Perchlorate [l,4-Bis(diphenylphosphino)butane](norbora-diene)rhodium Tetrafluroborate Catecholborane (1,5-Cycloocta-diene)[ 1,4-Bis(diphenylphosphino)butane]iridium(I) Tetrafluoro-borate (1,5-Cyclooctadiene)(tricyclohexylphosphine)(pyridine) iridium(I) Hexafluorophosphate Octacarbonyldicobalt Palladium (II) Chloride Tetrakis(triphenylphosphine)palladium(0) 2-Amino-3-picoline Benzylamine. 

The authors used a new type of substrate, e.g., 2-amino-3-picoline 7.1, which produces conventional substrates 12, which, in turn, form a five-membered ring 7.3 during a reaction with one component, such as an aldehyde. Other components, such as 1-alkenes, coordinate to the metal atom. Finally, the product 7.4 is formed by the couphng of l-aUcenes and aldehydes at the rhodium catalyst. 

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