Allylalkohole: nachhaltige Substrate für die katalytische enantioselektive Alkylierung

Enantioselective Dearomatization of Naphthol Derivatives with Allylic Alcohols by Cooperative Iridium and Brønsted Acid Catalysis

“…and nucleophiles.H owever,e xamples of successful utilization of naphthols in allylic substitution reactions are limited. [13] It is well known that the application of allylic alcohols in AAA reactions has been limited by the poorer leaving ability of the hydroxy group.T oo vercome this problem, several strategies,s uch as using high reaction temperature,o rL ewis or Brønsted acids,h ave been explored. [12] However,t he electrophiles involved in all cases were allyl carbonates.Because of the high synthetic step economy and positive environmental impact (water as the only stoichiometric by-product), the use of synthetically reliable alcohols instead of allyl carbonates in AAA reactions have become more and more popular.…”

“…Inspired by these results,aseries of chiral phosphoric acids were tested. could effectively improve the yield to greater than 60 %a nd enantioselectivity to greater than 87 %(entries [11][12][13]. (R)-PA2,( R)-PA4,a nd (R)-PA7 could also promote the reaction (entries 5, 7, and 10), and (R)-PA7 gave the best results with regard to both chemo-and enantioselectivity.…”

“…[12] However,t he electrophiles involved in all cases were allyl carbonates.Because of the high synthetic step economy and positive environmental impact (water as the only stoichiometric by-product), the use of synthetically reliable alcohols instead of allyl carbonates in AAA reactions have become more and more popular. [13] It is well known that the application of allylic alcohols in AAA reactions has been limited by the poorer leaving ability of the hydroxy group.T oo vercome this problem, several strategies,s uch as using high reaction temperature,o rL ewis or Brønsted acids,h ave been explored. [13a-e,14] In this context, some successful examples have been reported.…”

Gold(I)‐Catalyzed Enantioselective Intramolecular Dehydrative Amination of Allylic Alcohols with Carbamates

“…[1] With the potential to condense synthetic sequences and reduce waste streams, the dehydrative amination of allylic alcohols as a route to enantiomerically enriched allylic amines has gained considerable interest. [5] Carreira et al have reported the Ir I -catalyzed enantioselective amination of 1-cyclohexylprop-2-enol with sulfamic acid in 70 % ee. [5] Carreira et al have reported the Ir I -catalyzed enantioselective amination of 1-cyclohexylprop-2-enol with sulfamic acid in 70 % ee.…”

“…However, while the stereospecific amination of chiral secondary allylic alcohols has been demonstrated, [2][3][4] the enantioselective amination of allylic alcohols remains problematic. [5] Carreira et al have reported the Ir I -catalyzed enantioselective amination of 1-cyclohexylprop-2-enol with sulfamic acid in 70 % ee. [6] Hartwig et al have reported the Ir I /BPh 3 -catalyzed enantioselective intermolecular amination of primary allylic alcohols with aromatic amines with up to 94 % ee, but this method was restricted to cinnamyl alcohols in the absence of a stoichiometric Lewis acid promoter.…”