Ethylaluminum dichloride Reagent

The reagent generated by treatment of 3-trimethylsilyl-2-propenyllitliium and ethylaluminum dichloride, however, shows good to excellent selectivity for the aw//-diastereomer (86- >99%)9. 

Menthoxyaluminum dichloride (1). Mol. wt. 253.15. This reagent is prepared by reaction of (-menthol and ethylaluminum dichloride in heptane at —78°. 

Diphenyl-BINOL-derived chiral aluminum reagents are prepared in situ by addition of Ethylaluminum Dichloride or Diethylaluminum Chloride to 3,3 -diphenyl-BINOL. These chiral aluminum reagents promote the enantioselective Diels-Alder reaction of cyclopentadiene with the oxazolidone dienophile (eq 14). Endo products are obtained with a high level of asymmetric induction (>90% ee) however, a stoichiometric amount of the Lewis acid is required. The preparation and use of a C3 symmetric BINOL-derived boronate has been reported (eq 15). BINOL-B(OAr)3 complexes have recently been developed for the asymmetric Diels-Alder reaction with imines (eq 16). ... 

A variety of other Lewis acids such as titanium tetrachloride, boron trifluoride etherate, rMSOTf and ethylaluminum dichloride, all in dichloromethane, were found to be effective oupling reagents without causing decomposition of the products as with stannic chloride. Of he above Lewis acids, ethylaluminum dichloride was found to be the best, producing an a P atio of 2 3 in 71% yield. Titanium tetrachloride gave a 1 1.2 a P mixture in 61% yield. 

Related Reagents. Antimony(V) Fluoride Boron Trifluoride Etherate Diethylaluminum Chloride Dimethylaluminum Chloride Ethylaluminum Dichloride Methylaluminum Dichloride Tin(IV) Chloride Titanium(IV) Chloride Triethylaluminum Trimethylaluminum. 

Related Reagents. Diethylaluminum Chloride Dimethylalu-minum Chloride Ethylaluminum Dichloride. 

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