Carbo-BINAP

Figure 19.6 (a) Carbo-BINAP- and (b) glutaroyl-AMINAP-functionalized hyperbranched PEIs (x = 0.8, 2, 25) [22],... 

Table 19.2 Enantioselectivity of the asymmetric hydrosilylation of acetophenone for the different hyperbranched Carbo-BiNAP and AMiNAP iigands (in tetrahydrofuran (THF)/toiuene).

For the carbo-BINAP ligands attached to the hyperbranched PEIs, uniform high enantioselectivities of 93-94% ee and good activities were observed (Table 19.2) and thus the hyperbranched systems display the ideal behavior of the mononuclear reference ligands. 

The Rh-BINAP-catalyzed intramolecular Alder-ene cycloisomerization is very rapid and, therefore, sequentially Rh-catalyzed sequences for the efficient enantioselective generation of five-membered carbo- and heterocycles were envisioned. Korber et al. [21] reported the enantioselective rhodium-catalyzed cycloisomerization of alkyl and (hetero)aryl alkynyl allyl alcohols for the generation of aldehyde-bearing chiral 4-alkyl 3-alkylidene THFs and tetrahydro-furanones, which were converted into a,P-unsaturated carbonyl side chains in a one-pot manner via a concluding Wittig olefination in good yields. 

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