Studies On The Metal-catalyzed Addition Of Aryl-and Alkylboronic Acids To Tryptanthrins

Quaternary alcohols represent one of key structural motifs in various natural products and biologically active compounds,thus becoming important synthetic targets in the recent years.As one of the most important ways to create quaternary alcohols,additions of aryl boronic acid derivatives to ketones received continuous attention in recent years.Great achievements have been made in rhodium or palladium complexes promoted additions of aryl boronic acid derivatives to isatin,?-keto esters,2,2,2-trifluoroacetophenones,1,2-diketones and simple ketones,while only few examples revealed the catalytic ability of cheap metal salts in promoting similar transformations.On the other hand,despite these successes with addition reactions involving aryl boronic acids,the bulkier sp3-hybridized alkylboronic acids are rarely employed in such transformations.Based on the previous research on the catalytic addition reaction of tryptanthrins,we developed a simple Ni?acac?2 catalyzed effective 1,2-addition reaction of tryptanthrins,which revealed that both aryl-and alkylboronic acids are good participants and afforded indoloquinazolinone type quaternary alcohols with 30%-90% yield.Importantly,the reaction showed remarkably broad substrate scope and good functional group tolerance.This dissertation is consisted of four parts:In part one,the reviews focused on the development of metal catalyzed addition of organic boron reagents to ketones for the construction of quaternary alcohols.In part two,we reported a simple Ni?acac?₂ catalyzed 1,2-addition reaction of arylboronic acids to tryptanthrins,affording indoloquinazolinone type quaternary alcohols with good yields.In part three,we reported nickel catalyzed 1,2-addition reaction of alkylboronic acids to tryptanthrins,affording the desired products with 37%-68% yield.In part four,experimental procedures,characterization data for all the products and computational details.