Aldehydes cyclopropane-containing

Cyclopropane compounds containing the olefin isostere replacement for the amide bond were prepared using Julia olefination chemistry. Aldehydes 39 and 40 were obtained by LAAIH4 reduction of the chiral w-butyl esters of 32 and 33, respectively, followed by swera oxidation of the corresponding alcohols (Figure 22). Condensation of the (S)-N-BOC-cyclohexylalanine sulfone 41 with aldehyde 39 gave after treatment with 2% Na(Hg) and deprotection, the trans and cis olefin-amines... 

Similarly, the perfluoroacyl radical CF3C (—O)203 was obtained by photolysis of a cyclopropane solution containing dw-butyl peroxide and trifluoroacetaldehyde below -80 °C after abstraction of the aldehydic hydrogen atom, the trifluoroacetyl radical is formed. It decarbonylates above -80 °C and exhibits a coupling of 11.54 G with three equivalent 19F nuclei. 

In the Ambruticin synthesis reported somewhat later by E. Lee et al. [115, 116], cyclopropane—PT-sulfone building block 267 (Scheme 88) was condensed with aldehyde 266 in THF containing some HMPA. The effect of the countercation on the reaction course was examined. LHMDS provided 78% yield with a ratio of isomers EjZ 80/20. The change to NaHMDS resulted in higher selectivity EjZ 90/10 however, at the expense of the yield (63%). With KHMDS the selectivity turned out lower (63% yield, EjZ 50/50). 

Transient phosphorylcarbenes also react with functionalized alkenes, including those containing aldehydes and acetals, affording the corresponding cyclopropanes (Table 2). 

Cyclopropanecarbaldehydes have been converted to the corresponding (dipyrrolidinometh-yl)cyclopropanes by reacting the aldehydes with pyrrolidine in an organic solution containing sodium carbonate. For example, formation of 7 from aldehyde 6. The yields... 

Hydrolysis of the pyrethroids may occur prior to hydroxylation. For dichloro groups (i.e., cyfluthrin, cypermethrin and permethrin) on the isobutenyl group, hydrolysis of the trans-isomers is the major route, and is followed by hydroxylation of one of the gem-dimethyls, the aromatic rings, and hydrolysis of the hydroxylated esters. The cis-isomers are not as readily hydrolyzed as the tran -isomers and are metabolized mainly by hydroxylation. Metabolism of the dibromo derivative of cypermethrin, deltamethrin, is similar to other pyrethroids (i.e., cyfluthrin, cypermethrin, and permethrin) that possess the dichloro group. Type 11 pyrethroid compounds containing cyano groups (i.e., cyfluthrin, cypermethrin, deltamethrin, fenvalerate, fenpropathrin, and fluvalinate) yield cyanohydrins (benzeneacetonitrile, a-hydroxy-3-phenoxy-) upon hydrolysis, which decompose to an aldehyde, SCN ion, and 2-iminothia-zolidine-4-carboxylic acid (TTCA). Chrysanthemic acid or derivatives were not used in the synthesis of fenvalerate and fluvalinate. The acids (i.e., benzeneacetic acid, 4-chloro-a-(l-methylethyl) and DL-valine, Af-[2-chloro-4-(trifluoromethyl) phenyl]-) were liberated from their esters and further oxidized/conjugated prior to elimination. Fenpropathrin is the oifly pyrethroid that contains 2,2,3,3-tetramethyl cyclopropane-carboxylic acid. The gem-dimethyl is hydroxylated prior to or after hydrolysis of the ester and is oxidized further to a carboxylic acid prior to elimination. 

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