Acrolein dimethylacetal

The acrolein dimethylacetal is reduced by the CrCl2 generating an active species that adds to the aldehyde. 

Figure 6. Hydroformylation of acrolein dimethylacetal. Synthesis of partially protected 1,4-...

CTotonaIdehyd.climethylaoetal 1 n 788. K-Methyl-acrolein-dimethylacetal 1, 731. Acetol-pro]>ylather 1, 823. FropionylcarbinoI-SthyliUber 1, 827,1420. Meth rl.[a. thozy. tliyl]-ketOQ 1, 829,... 

We tested several routes to the aldehyde boronate 48. The following one turned out to be most reliable Acrolein-dimethylacetal was subjected to rhodium catalyzed hydroboration to give 49. Acetal cleavage was achieved with yet another mild reagent, cerium-montmorillonite in moist dichloromethane 24) to give 98% of the desired aldehyde 48. (25)... 

Villsmeier reaction on the dimethylacetal of methoxyacetaldehyde (141) with phosgene and dimethyIformamide affords the acrolein derivative, 142. Condensation of this with guanidine gives the pyrimidine, 143. (The enamine can be viewed as a latent aldehyde-the dimethylamino group is probably lost in the course of an addition elimination reaction with one of the guanidine groups.) This pyrimidine serves as starting material for sulfameter (111). ... 

Cationic cycloadditions. Ionization of p-benzoquinone monoacetals is induced by MejSiOTf in highly polar media (LiClO /EtOAc) and the carbocations are captured in situ by alkenes to give bicyclo[3.2.1]octene derivatives. A synthesis of 2-(l -phenylethoxy)-8-oxabicyclo[3.2.1]oct-6-en-3-one in good enantiomeric purity from furan and a mixed acetal of 2-(triethylsiloxy)acrolein (prepared from pyruvaldehyde dimethylacetal in three steps) is promoted by MejSiOTf. 

Electrophile = acrolein, methyl acrylate, acrylonitrile, 2-cyclopentene-1 -one, benzaldehyde dimethylacetal, 2,2-dimethoxypropane, 2-cyclohexene-1-one or dimethylfurmarate... 

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