Oximes aldehydes

A"-Octadienylatiori, rather than 0-octadienylation, of aldehyde oximes takes place to give the nitrone 37 as an intermediate, which undergoes 1.3-dipolar addition to butadiene, yielding the isoxazolidine 38[39],... 

Besides a-halocarbonyl compounds, a-mercaptoketones and acids are also used for the preparation of thiazoies from nitriles and aldehydes oximes. 

Ru3(CO)i2, CO, 20 atm, 4 h, 100°. These conditions reduce the oxime to an imine that is easily hydrolyzed with water. Aldehyde oximes give low yields of nitriles. 

Trichlor-nitro-methan wird in waBrig-alkoholischer Schwefelsaure stufenweise bis zum Methylamin reduziert, wobei die ZwischenstufenTrichlor-nitroso-methan, Dichlor-form-aldehyd-oxim und N-Methyl-hydroxylamin6 isoliert werden konnen. Als Kathode dient ein von Kiihlfliissigkeit durchstromtes Zinn-Rohr6. 

Benzoxazoles are produced in high yield from a-acylphenol oximes by a Beckmann rearrangement using zeolite catalysts <95SC3315>. The reaction of the o-benzoquinone 40 with aromatic aldehyde oximes produces the benzoxazoles 41 <95ZOR1060>. The fused oxazolium salts 43 (R = Me, Et, Pr , or Ph R2 = Me or Pr ) are formed from tropone and nitrilium hexachloroantimonates 42 <96JPR598>. 

Depending on the nature of the substrates, selectivity could be completely reversed between the two isomeric products. For example, switching R1 group between Buc and Ph gave high yields of the first and second product structures, respectively. The authors noted that the reaction did not proceed if the imine contained an ortho-MeO group at R2 or if the imine was replaced with an aldehyde, oxime, or hydrazone. The catalytic cycle is initiated by C-H activation of the imine, that is, the formation of a five-membered metallocycle alkyne insertion affords the intermediate drawn in Scheme 69. It is noteworthy that this is the first report of catalytic synthesis of indene derivatives via a C-H insertion mechanism (C-H activation, insertion, intramolecular addition). 

Di-2-pyridyl sulphite (343) (from 2-pyridone and thionyl chloride in the presence of triethylamine) transforms primary aliphatic and aromatic amines RNH2 into N-sulphinylamines RN=S=0 and it dehydrates amides ArCONH2 to aryl cyanides, aldehyde oximes RCH=NOH (R = Cxlf 7. 4-MeOCgH4 or PhCH=CH) to the cyanides RCN and A-alkyl- and TV-ary Iformamides RNHCHO to isocyanides RNC. Aliphatic and aromatic... 

SPME Fiber. A 65 pm poly(dimethylsiloxane)/divinyl benzene (PDMS/DVB) fiber coating (Supelco, Bellefonte, PA) was used in this method. This fiber coating was selected for its ability to retain the derivatizing agent and for its affinity for the PFBOA-aldehyde oxime (7). 

C15H13N3O 1 -(Pheny Imethy 1)- IH-benzimidazole-2-carbox-aldehyde oxime Extraction-photometric Co, Cu 3... 

Geminal 1H,15N couplings are a sensitive indicator of the stereochemistry of imino compounds, e.g., the cis orientation of the lone electron pair at the nitrogen of (Z)-2-furancarbox-aldehyde oxime enhances the coupling considerably compared with the E-isomer (numbers are Vh.hn)293 295 An analogous sequence has been observed for A-alkylaldimincs, e.g., /V-(methyl)benzenemethanimine296. 

Aldehyde oximes and primary nitroalkanes arc converted to nitriles by PI3 or P2143 in combination with triethylamine. 

Cyanothiophene is most conveniently derived from the aldehyde oxime by dehydration (equation 23), but has also been obtained by reaction of the 2-thienyl Grignard reagent or 2-thienyllithium with cyanogen chloride. Activated halogens are readily displaced by cyanide ion (equation 24 Section 3.14.2.7). 

Mechanistic work has been done on reduction of all three aldehyde oximes 45 the products of macroscale reduction are the picolylamines (Scheme 16).66 These amines are more conveniently made from the nitrile at present because the aldehyde precursor is difficult to make. 

Azidobenzaldehyde, 2693 f Aziridine, 0859 Azobenzene, 3477 Azoformamide, 0812 Azoxybenzene, 3479 Benz aldehyde oxime, 2756 Benzyl chloride, 2734 4-Bromoaniline, 2289... 

Since oximes are more stable to oxidation and often more available than the corresponding carbonyl compounds they also can be used as starting material for the cyclizations. For instance, quinoxaline-2-aldehyde oxime 49a as well as ketoxime 49b are converted by hydrazine in acidic medium into flavazoles 50 (Scheme 14) (01JHC829). Hydroxylamine, which is liberated in the first step, may act as a hydride ion acceptor. This minimizes using a large excess of arylhydrazine or any another oxidant. 

Reactions of perfluoroolefins with aliphatic aldehyde oximes lead to cyclization product 87 without a rearrangement of the carbon skeleton. 

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