62222-04-2

Upstream product

• 14593-43-2 benzyl allyl ether 
• 74-95-3 1,1-dibromomethane 
• 60656-87-3 benzyloxyacetoaldehyde 
• 124568-19-0 (2S)-2-benzyloxy-3-fluoropropanal 
• 100-39-0 benzyl bromide 
• 124588-26-7 (2S)-1-trifluoroacetyloxy-1-tolylthio-2-benzyloxy-3-fluoropropane 
• 124568-12-3 (2S,R_S)-2-benzyloxy-3-fluoro-1-(p-tolylsulphinyl)propane 
• 50-00-0 formaldehyd 

Downstream Products

• 62221-97-0 4-Benzyloxypenta-2.4-diensaeure 

Relevant academic research and scientific papers

Electrophile-Dependent Alkylations of Lithiated 4-Alkoxyalk-4-enenitriles

Alkylations of acyclic, lithiated 4-alkoxyalk-4-enenitriles are highly diastereoselective with an unusual electrophile-dependent preference. Alkyl halides, sulfur, chlorine, and acyl cyanide electrophiles intercept a series of lithiated 4-alkoxyalk-4-enenitriles to install contiguous tertiary-quaternary stereocenters with high diastereoselectivity, whereas acylations with ester and carbonate electrophiles are modestly selective. The diastereoselectivity is consistent with electrophilic attack on the most accessible face of the lithated nitrile for most electrophiles except ester and carbonate electrophiles, which likely precoordinate the lithiated nitrile before acylation. Intercepting the lithiated 4-alkoxyalk-4-enenitriles with a range of electrophiles provide insight into the criteria for otherwise challenging diastereoselective alkylations and acylations of acyclic nitriles.

Sequential asymmetric catalysis in Michael-Michael-Michael-aldol reactions: Merging organocatalysis with photoredox catalysis in a one-pot enantioselective synthesis of highly functionalized decalines bearing a quaternary carbon stereocenter

An expedited method has been developed for the enantioselective synthesis of highly functionalized decaline systems containing seven contiguous stereogenic centers with high enantioselectivities (>99% ee). The one-pot methodology comprises a cascade of organocatalytic double Michael-photocatalyzed Michael-aldol reactions of ethyl 2-bromo-6-formylhex-2-enoate, β-alkyl-α,β-unsaturated aldehydes, and α-alkyl-α, β-unsaturated aldehydes. The structure and absolute configuration of an appropriate product were confirmed by X-ray analysis.

Chiral primary amine catalyzed asymmetric epoxidation of α-substituted acroleins

1,1-Disubstituted terminal alkenes remain challenging substrates in asymmetric epoxidation reactions. In this study, chiral primary amines are shown to catalyze the asymmetric epoxidation of α-substituted acroleins, a versatile type of 1,1-disubstituted t

Rapid organocatalytic aldehyde-aldehyde condensation reactions

We report the results of the systematic optimization of the α-methylenation of aldehydes with aqueous formaldehyde. A simple combination of a secondary amine catalyst and a weak acid co-catalyst has been identified, allowing access to α-substituted acroleins in a matter of minutes. In the absence of formaldehyde, the catalytic system promoted the self-condensation reaction of α,β-unsaturated aldehydes. Both of these reactions exhibited linear relationships between co-catalyst acidities and reaction rates. A second-order dependence of catalyst concentration was observed, pointing to the involvement of two molecules of the ammonium catalyst in the rate-determining step. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.

Mild organocatalytic α-methylenation of aldehydes

A rapid and extremely convenient method for α-methylenation of aldehydes with aqueous formaldehyde is described. Two optimal catalytic systems are presented that allow short reaction times and afford the functionalized products in good to excellent yields (up to 99%) and chemoselectivity.

Amino acid catalyzed neogenesis of carbohydrates: A plausible ancient transformation

Hexose sugars play a fundamental role in vital biochemical processes and their biosynthesis is achieved through enzyme-catalyzed pathways. Herein we disclose the ability of amino acids to catalyze the asymmetric neogenesis of carbohydrates by sequential cross-aldol reactions. The amino acids mediate the asymmetric de novo synthesis of natural L- and D-hexoses and their analogues with excellent stereoselectivity in organic solvents. In some cases, the four new stereocenters are assembled with almost absolute stereocontrol. The unique feature of these results is that, when an amino acid is employed as the catalyst, a single reaction sequence can convert a protected glycol aldehyde into a hexose in one step. For example, proline and its derivatives catalyze the asymmetric neogenesis of allose with > 99% ee in one chemical manipulation. Furthermore, all amino acids tested catalyzed the asymmetric formation of natural sugars under prebiotic conditions, with alanine being the smallest catalyst. The inherent simplicity of this catalytic process suggests that a catalytic prebiotic "gluconeogenesis" may occur, in which amino acids transfer their stereochemical information to sugars. In addition, the amino acid catalyzed stereoselective sequential cross-aldol reactions were performed as a two-step procedure with different aldehydes as acceptors and nucleophiles. The employment of two different amino acids as catalysts for the iterative direct aldol reactions enabled the asymmetric synthesis of deoxysugars with > 99% ee. In addition, the direct amino acid catalyzed C2+C 2+C2 methodology is a new entry for the short, highly enantioselective de novo synthesis of carbohydrate derivatives, isotope-labeled sugars, and polyketide natural products. The one-pot asymmetric de novo syntheses of deoxy and polyketide carbohydrates involved a novel dynamic kinetic asymmetric transformation (DYKAT) mediated by an amino acid.

Stereoselective synthesis of fluorinated isoxazolidines and 2,3- dihydroisoxazoles: A cycloadditive route to enantiomerically pure amino fluoro alcohols

3-(Fluoroalkyl)isoxazolidines 6 and -2,3-dihydroisoxazoles 8 have been obtained in enantiomerically pure form with good diastereoselectivity by 1,3- dipolar cycloaddition of diethyl fumarate and dimethylacetylene dicarboxylate, respectively, to the chiral fluorinated nitrone (R)-5. The latter has been prepared from the β-fluoromethyl-β-oxo sulfoxide (R(S)-1, by a synthetic sequence where the chiral and enantiomerically pure sulfinyl function acts as a removable source of chirality. Reductive opening of isoxazolidines 6 then afforded amino fluoromethyl diols 7 in good yields.

Preparation of α-substituted acroleins via the reaction of aldehyde or the corresponding ozonide with dihalomethane and diethylamine

Treatment of aldehydes or the corresponding ozonides with a mixture of dibromomethane and diethylamine afforded α-substituted acroleins in modest to good yields. The β-carbon of the acrolein (nc, n = 1-16) derived from dibromomethane. Functional groups, s

Preparation of α-Substituted Acroleins via the Reaction of Aldehyde with Dihalomethane and Diethylamine

Treatment of ozonides or aldehydes with a mixture of dihalomethane and diethylamine in dichloromethane affords α-substituted acroleins in good yields, the β-carbon of the acrolein being derived from dihalomethane; the relative rates and yields are in the following order: CH2I2 > CH2Br2 > CH2Cl2.