Aldehydes epoxides from

Other modifications of the polyamines include limited addition of alkylene oxide to yield the corresponding hydroxyalkyl derivatives (225) and cyanoethylation of DETA or TETA, usuaHy by reaction with acrylonitrile [107-13-1/, to give derivatives providing longer pot Hfe and better wetting of glass (226). Also included are ketimines, made by the reaction of EDA with acetone for example. These derivatives can also be hydrogenated, as in the case of the equimolar adducts of DETA and methyl isobutyl ketone [108-10-1] or methyl isoamyl ketone [110-12-3] (221 or used as is to provide moisture cure performance. Mannich bases prepared from a phenol, formaldehyde and a polyamine are also used, such as the hardener prepared from cresol, DETA, and formaldehyde (228). Other modifications of polyamines for use as epoxy hardeners include reaction with aldehydes (229), epoxidized fatty nitriles (230), aromatic monoisocyanates (231), or propylene sulfide [1072-43-1] (232). 

The development of new methods for carbon-caihon bond formation is at the heart of organic synthesis. The most desirable methods are those that are easily practiced at scale, operate near ambient temperature, and that do not require strong acid or base. David C. Forbes of the University of South Alabama and Michael C. Standen of Synthetech in Albany, OR report (Organic Lett. 5 2283,2003) that the crystalline salt 2, which can be stored, smoothly converts aldehydes to epoxides, without any additional added base. The reaction is apparently proceeding by the loss of CO, from 2 to give the intermediate sulfonium methylide. 

The dianion derived from but-2-ynoic acid reacts with aldehydes to give 5-hydroxyalk-2-ynoates (539). Partial reduction over a Lindlar catalyst and acid-catalyzed cyclization of the resulting enoate gives the dihydropyran-2-one (78LA337). The route is exemplified by the synthesis of the naturally occurring massoia lactone (Scheme 200). In previous work (46JCS954) the hydroxyalkynoic acids themselves, obtained from epoxides and acetylene, were used. 

A novel approach to the asymmetric synthesis of epoxides, allylic alcohols, a-amino ketones, and a-amino aldehydes from carbonyl compounds through a,/i-epoxy sulfoxides using the optically active p-tolylsulfmyl group to induce chirality./. Org. Chem. 1989, 54, 3130-3136. 

Alcohols can also be obtained from epoxides, aldehydes, ketones, esters, and acid chloride as a consequence of C-C bond formation. These reactions involve the addition of carbanion equivalents through the use of Grignard or organolithium reagents. 

Oxametallacycle formation from aliphatic alkoxides could occur via C-H scission at the p position, or from epoxides by C-O scission to open the ring. The subsequent C-H and C-C bond activation steps are less clear than those of the aldehydes above. For the oxametallacycle formed from the ethoxide, C-C scission must release CH2 or perhaps CH... 

SECTION 54 Aldehydes from Ethers, Epoxides, and Thloethers... 

All reactive functions, apart from epoxide, require a preliminary amine activation step prior to chemical coupling or a reduction after grafting step (aldehyde). The quantities of chemically immobilized ODN are in the same order of magnitude than those grafted during adsorption (less than 1 mg nr2) which let one suppose that the amine functions carried by the bases also react... 

Trifluoroacetimidoyllithiums 75 have been prepared from imidoyl iodides by reaction with n-BuLi at — 78 °C and have been trapped with aldehydes, ketones, epoxides,... 

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