Carboamination morpholines

The 1,4-carboamination has been extended to the use of vinyl bromides [37-39]. The use of morpholine or piperidine as the external nucleophile led to a 1,4-addition to the 1,3-diene via a (7r-allyl)palladium intermediate. An example that leads to a carbocyclization via vinylpalladation is shown in Eq.(19). 

Stereoselective Synthesis of 3,5-Disubstituted Morpholines After successful use of the carboamination reaction of amino alkenes for the synthesis of pyrrolidines, pyrazolidines, and piperazines, the same group reported on the synthesis of another important heterocyclic scaffold morpholine. Morpholines are also widely applicable and present in various biologically important natural and... 

The 3,5-disubstituted morpholine derivatives have been obtained in good yield and as a single stereoisomer using a carboamination reaction starting from a chiral a-amino alcohol precursor. In this approach, 2-subsituted (9-allyl ethanolamine 59 has been synthesized from A -Boc-pro-tected amino alcohol by simple (9-allylation, Boc-deprotec-tion, and Pd-catalyzed A -arylation reactions. For substrate 59 when treated with an external aryl bromide and Pd(OAc)2 catalyst in the presence of NaOt-Bu base and... 

SCHEME 40.13. Carboamination reaction of substituted chiral amino alcohol synthesis of disubstituted morpholines. 

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