Cyclopropyl acetophenone

The scope and limitations for transfer hydrogenation employing either the iron porphyrin system or the combination of iron compound/terpy/PPhs are listed in Table 8. In most cases, the FeCVterpy/PPhs system displays a higher activity. Except for chloromethyl- and cyclopropyl-acetophenone, the desired products were obtained in good to excellent yields. It should be noted that a ring opened product was not observed when cyclopropyl acetophenone was employed. Hence, a radical-type reduction pathway was excluded and a hydride mechanism appeared to be reasonable. 

I) According to one of the methods, the starting material is cyclopropyl benzene, which is acetylated, and the l-acetyl-4-cyclopropyl benzene obtained being converted by Schmidt rearrangement into 4-cyclopropyl acetophenone. The hydrolysis of the latter yields 4-cyclopropyl aniline ... 

C2jH3 07 67212-74-2) see Alclometasone dipropionate 2 -hydroxy-4 -(3-methyl-2-butenyloxy)acetophenone (C,3H] 03 24672-83-1) see Sofalcone 2-hydroxy-2-methylbutyric acid ethyl ester (C7H14O3 77-70-3) see Paramethadione 2-hydroxy-2-methylbutyronitrile (Ci H NO 4111-08-4) see Paramethadione 5(R)-(hydroxymethyl)-2-cyclopenten-l(R)-ol (C(jH,(,02 143395-28-2) see Abacavir 2-[l-(hydroxymethyl)cyclopropyl]acctonitrile (QH9NO 152922-71-9) see Montelukast sodium ( )-cis-2-hydroxymethyl-Af,Af-diethyl-l-phenylcyclo-propanecarboxamide... 

Acetone- or acetophenone-sensitized irradiation of the enones yields the reeurranged ketones (213, 214) which are described as useful substrates for the synthesis of polyquinane natural products. The enones (215) can be converted by photosensitized irradiation into the diquinanediones (216). Irradiation of (215) in acetone gives a low yield of the tricyclic ketone (217). This ketone, while stable in the dark, is photochemically converted into the diquinanedione (215). The authors present evidence that this conversion results from fission of the cyclopropyl bond to yield the biradical (218). Demuth and Hinsken have reported the use of the oxardi-ir-methane rearrangement in the synthesis of annelated triquinanes. Thus the photo conversion of the enone (219) affords the tetracyclic ketone (220,72%). In an analogous reaction the enone (221) is converted into the isomeric ketone (222,70%). ... 

This approach has been used, for example, to find whether the intramolecular photocycloaddition reaction of the triplet excited cyclopropyl-substituted 4-(buteny-loxy)acetophenone 220 proceeds via the 1,4-biradical 221 (Scheme 6.87).827 This presumption was confirmed by identifying the three rearrangement cyclization products 222 224. Because the rate constant of the cyclopropylcarbinyl radical opening to the allylcarbinyl radical is known to be 7 x 107 s 1,828 it was suggested that the rate constant for the formation of the (not observed) or// o-photocycloaddition adduct (225) must be less than 3 x 106s This technique comparing the rate constants of two parallel processes, of which one is known is often referred to as a kinetic (or radical) clock 29... 

The first compound selected for this study was the azadiene 1. Previous studies demonstrated that tetraphenyl-substitution in positions 3 and 5 of the P,y-unsaturated s) tem promotes efficient DPM, ODPM, and 1-ADPM reactions in acyclic 1,4-dienes," P,y-unsaturated aldehydes, and l-aza-1,4-dienes, respectively. Based on these precedents, the 2-azadiene 1 was considered to be a suitable candidate to undergo rearrangement of the di-7l-methane type. Triplet-sensitized irradiation of azadiene 1, using acetophenone, for 25 min, afforded two new products that were identified as the cyclopropyl imine 2 (11%) and the vinylaziridine 3 (3%) (Scheme 1). Compound 2 hydrolyzes to the corresponding cyclopropyl amine during isolation. ... 

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