Dimethylaluminium chloride

Diethylaluminium bromide, 1670 Diethylaluminium chloride, 1671 Diisobutylaluminium chloride, 3064 Dimethylaluminium bromide, 0882 Dimethylaluminium chloride, 0883 Ethylaluminium bromide iodide, 0841 Ethylaluminium dibromide, 0842 Ethylaluminium dichloride, 0843 Ethylaluminium diiodide, 0844 Hexaethyltrialmninimn trithiocyanate, 3695 Methylaluminium diiodide, 0423 Triethyldialuminium trichloride, 2556 Trimethyldialuminium trichloride, 2556 See Other ALKYLMETAL HALIDES... 

Enal (54) undergoes intramolecular carbonyl-ene cyclization to give cis- and trans-alcohols (55). Lewis acids such as boron trichloride and tin tetrachloride (and also dimethylaluminium chloride ) give predominantly the cis product, while the preference is reversed with the bulky MeALAr2(Ar = OC6H2 -Br-2, 6-di-Bu ). Open and closed chair-like transition states are considered and compared with previous... 

Chien, J. C. W. Kinetics of ethylene polymerization catalyzed by bis(cyclo-pentadienyl)-titanium dichloride-dimethylaluminium chloride. J. Amer. Chem. Soc. 81, 86 (1959). 

Diethylaluminium bromide, 1664 Diethylaluminium chloride, 1665 Diisobutylaluminium chloride, 3059 Dimethylaluminium bromide, 0878 Dimethylaluminium chloride, 0879 Ethylaluminium bromide iodide, 0837 Ethylaluminium dibromide, 0838 Ethylaluminium dichloride, 0839 Ethylaluminium diiodide, 0840 Hexaethyltrialuminium trithiocyanate, 3688 Methylaluminium diiodide, 0422 Triethyldialuminium trichloride, 2551 Trimethyldialuminium trichloride, 1288 See ALKYLALUMINIUM DERIVATIVES (references 1,2)... 

Alder reaction, catalysed by dimethylaluminium chloride, has been employed in a new total synthesis of pseudomonic acids A and C from hexa-1,5-diene. In a further study of the ionophore antibiotic lasalocid (3), it has been subjected to Mannich and Baeyer-Villiger reactions. The former took an unusual course in that the carboxyl was replaced by an aminomethyl group. The natural ionophore X-14547A (4) has been synthesized from two separately prepared segments (5) and (6) of the molecule. ... 

Snider et al. have previously reported that the dimethylaluminium chloride catalysed sequential ene reactions of exocyclic olefins leads to cyclohexanols. They now find that in the presence of excess acrolein, the aluminium alkoxide... 

Rodini and Snider demonstrated that dimethylaluminium chloride catalyses an ene reaction between aldehydes and alkenes. As a follow-up they showed that terminal alkynes give a similar reaction with formaldehyde". ... 

Heterodiene synthesis. Bis(trimethylsilyl) selenide in toluene treated under argon with ca. 2 eqs. dimethylaluminium chloride in hexane, stirred for 15 h at 100°, the solvent removed carefully under reduced pressure, THF, cyclopentadiene, and fluorenone added sequentially to the residue, and heated under reflux for 16h - cycloadduct. Y 77%. The method is also applicable to the in 5//w-generation of simple dialkyl selenoketones. F.e.s. M. Segi et al.. Tetrahedron Letters 30, 2095-8 (1989). 

The nickel/dimethylaluminium chloride-catalysed 3 -I- 2-cycloaddition reactions between cyclopropyl ketones and alkynes produced cyclopentene cycloadducts. 

Further variations on these reactions are illustrated by the reaction of nitriles with dimethylaluminium chloride or hydride ... 

The endIcT-selective hetero Dids-Alder reaction of chiral oxazolidones 12 with (Z)-l-acetoxy-2-ethoxyethene yields the 1-substituted glycals 13 as the major products when catalysed with dimethylaluminium chloride, and 14 as the major products when catalysed with trimeth silyl triflate. Compounds 13 (R = Et)and 14 (R = Et) were subsequently converted into ethyl P-D-mannopyranoside and ethyl 3-L-mannopyrannoside, respectively. ... 

Neither dimethyl nor diisobutyl aluminium chloride undergo the reaction under identical conditions. Therefore, the process was studied in greater detail. As simple model compounds a,p-unsaturated N-acyl oxazolidones 22 were used. It could be demonstrated that dimethylaluminium chloride catalyzes the transfer of higher alkyl groups from other alkylaluminium compounds. But, it is unable to deliver the methyl group to the acceptors 2 2 (eq.9). 

Other Unsaturated Alcohols. Dimethylaluminium chloride has been found to be a useful catalyst for the ene reaction of aliphatic and aromatic aldehydes with alkenes (Scheme 16) to produce homoallylic alcohols/ by acting as a mild Lewis acid and proton scavenger rapid decomposition of the product alcohol-Lewis acid complex (42), a strong proton acid species, gives methane and a non-acidic alkoxide, thus avoiding protonation of the carbon-carbon double bond in the alkene or ene adduct, 1,1-Disubstituted alkenes are the most reactive under these conditions, and the yields of ene additions to formaldehyde are also improved. 

Homoallylic Alcohols. Full details have appeared of the ene reactions of aldehydes with alkenes, catalysed by dimethylaluminium chloride (Scheme 8) (6, 166). ... 

Thus, one equivalent of dimethylaluminium chloride has been shown to result in an ene reaction to give the alcohol (46), compared to the use of two equivalents, which produces complex mixtures by means of cation-olefin cyclizations. ... 

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