Alkenes reaction with aldehydes

Methylarsine, trifluoromethylarsine, and bis(trifluoromethyl)arsine [371-74-4] C2HAsF, are gases at room temperature all other primary and secondary arsines are liquids or solids. These compounds are extremely sensitive to oxygen, and ia some cases are spontaneously inflammable ia air (45). They readily undergo addition reactions with alkenes (51), alkynes (52), aldehydes (qv) (53), ketones (qv) (54), isocyanates (55), and a2o compounds (56). They also react with diborane (43) and a variety of other Lewis acids. Alkyl haUdes react with primary and secondary arsiaes to yield quaternary arsenic compounds (57). 

Osmium tetroxide, reaction with alkenes, 235-236 toxicity of, 235 Oxalic add, structure of, 753 Oxaloacetic acid, structure of, 753 Oxetane, reaction with Grignard reagents, 680 Oxidation, 233, 348 alcohols, 623-626 aldehydes, 700-701 aldoses, 992-994 alkenes, 233-236 biological, 625-626 phenols, 631 sulfides, 670 thiols, 668... 

Another interesting biooxygenation reaction with alkenes, recently identified, represents an enzymatic equivalent to an ozonolysis. While only studied on nonchiral molecules, so far, this cleavage of an alkene into two aldehydes under scores the diversity of functional group interconversions possible by enzymatic processes [121,122]. 

In addition to undergoing cycloaddition reactions with alkenes and al-kynes, silenes readily undergo cycloaddition reactions with heteroatom multiple bonds such as C=0 and C=N, most commonly when the trapping reagent for the silene is either an aldehyde, ketone, or imine. In many... 

The photochemical generation of hydroxy-o-quinodimethanes from o-alkylbenz-aldehydes may be followed by a thermal Diels-Alder reaction with alkenes (Scheme 9.33) [54]. This reaction is effective in both intermolecular and intramolecular modes, and has been applied to the synthesis of various natural products [55],... 

Reaction of aldehydes 881 with alkenes in the presence of IPy2BF4 gives benzothiophenes 883. The reaction involves addition of the alkenes to intermediates 882, ring opening, and loss of HI (Scheme 135) <2006CEJ5790>. 

Ozone, while somewhat inconvenient to use, is way qiecific in its reactions with alkenes. It is widely employed for selective synthesis, for qualitative and quantitative analysis of unsaturated compounds, and for studying the position of double bonds in macromolecules. The nature of the products obtained from ozonolysis reactions is determitted by the way in which the reaction is carried out Different workup procedures (hydrolytic, reductive or oxidative) can be used to produce alcohols, aldehydes, ketones, carboxylic acids or esters. 

Reaction of alkenes with carbonyl compounds or carbonyl derivatives in the presence of Lewis acids, the ene reaction, enables the stereoselective preparation of highly functionalized compounds. Copper Lewis acids activate both aldehydes and imines in ene reactions. Evans has reported that Cu(II) Lewis acids catalyze glyoxylates in reactions with alkenes (Sch. 56) [103]. The homoallylic alcohols 257 and 259 are produced in high yield and enantioselectivity. The bis aquo complex 260 is a readily prepared and air-stable catalyst and gave high chemical yield and excellent selectivity in the ene reactions. Another point of note is that catalysts 260 and 261 furnish enantiomeric products even though they differ from each other only by the substituent at the 4-posi-tion of the oxazoline. 

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