7e-phenyl

Ethyl 1 -substituted 7-hydroxy-5-oxo-1,2,3,5-tetrahydropyrido[ 1,2,3-<7e] quinoxaline-6-carboxylates were reacted with A- [3,5-bis(trifluoromethyl)-phenyl]methyl methylamine to yield carboxamides (01MIP12). 

S,4S,5 E,7E)-3-Amino-4-hydroxy-6-methyl-8-(4-bromophenyl)-octa-5,7-dienoic acid [Aboa = Br-Ahmp, Br-Apoa], (2S,3S,8S,9S)-3-Amino-9-methoxy-2,6,8-trimethyl-10-phenyl-deca-4,6-dienoic acid (Adda). 3-Amino-2,4-dimethylpentanoic acid (Admpa). (2S,3R,5S)-3-amino-2,5,9-trihydroxy-10-phenyldecanoic acid (Ahda). j3-Aminoisobutyric acid (jS-AiB). (3S,4S,5E,7E)-3-Amino-4-hydroxy-6-methyl-8-phenylocta-5,7-dienoic acid [Ahmp (Faulkner) or Apoa (Fusetani)]. (2S,3R,5R)-3-Amino-2,5-dihydroxy-8-phenyloctanoic acid (Ahoa). 3-Aminopentanoic acid (Apa /5-Apa). (2R,3R)-3-Amino-2-methylbutanoic add (Amba). 3-Amino-2-methylhexanoic acid (Amha). 3-Amino-2-methyl-7-octynoic add (Amoa, Amoya). 3-Amino-7-octynoic add (Aoya). (2S,3R)-3-Amino-2-methylpentanoic acid (Map). http // www.ncbi.nlm.nih.gov/ Taxonomy/ tax.html... 

When phenylacetylenes (3 mol), tellurium dioxide (1 mol), and a lithium halide (14-18 mol) were refluxed in acetic acid, 3-halobenzotellurophenes were obtained in yields ranging from 21 to 92%2. A tellurium(IV) acetate halide, formed from tellurium dioxide, lithium halide, and acetic acid, probably adds to the carbon-carbon triple bond of the phenylacetylene. The intermediary 2-phenyl-2-haloethenyl tellurium acetate halide cyclizes probably by loss of acetic acid. The 3-halobenzotellurophene Te, 7e-acetate halide is then reduced to 3-halobenzotellurophene by an excess of the phenylacetylene. Diphenylacety-lene and diphenyldiacetylene did not react under these conditions. 

Dicyanomethylidene)-2,6-di-/ert.-butyl (or phenyl)-4//-tellurin was oxidized by per-oxyacetic acid and converted to the 7e,7e-diacetate by acetic acid in dichloromethane1. 

Phenyl-7-methoxybenzotellurinium perchlorate was oxidized to the 7h,7e -dioxide of the 4-(4//-l-benzotellurin-4-ylidene)-4//-l-bcnzotellurin by triphenylphosphane oxide at 220° or by air in pyridine in the presence of triphenylphosphane1. 

A complete removal of the conjugated Jt system, as in the cydohexyl analogue 7c, also resulted in a minor decrease in enantioselectivity (to 85% ee, entry 12) as compared to the phenyl analogue 6b (94% ee, entry 1). However, it is pertinent to note that this decrease was found to be more substantial when the less bulky catalyst 22 was employed (37% ee at rt and 59% ee at 20 °C) [12b], demonstrating the superiority of Sigamide (35). With the less sterically hindered isopropyl derivative 7d, the enantioselectivity dropped to 62% ee (entry 13). On the other hand, the sterically much more congested tert butyl derivative 7e reacted sluggishly and the enantioselectivity was found to further decrease (entry 14) [12h]. 

The same trend in the electronic effects is observed experimentally for the urazole-bridged 4,5-diazacyclopentane-l,3-diyl triplet diradicals 7 (Table 5), which were chosen to probe for the effect of heteroatom substitution on the D parameter. Substitution of a phenyl by a methyl group in 7d also results in an increased D value in 7g, but is less effective (18%) as seen in the carbocyclic derivatives. These results are in line with the earlier reported [17] D values of iV-phenylurazole-bridged cyclopentene-1,3-diyl triplet diradicals 7a-c (cf. Table 1). As for the carbocyclic diradicals, the electronic substituent effects are reproduced in the diradicals 7e and f not only qualitatively but quantitatively (Table 5). For example, the spin-accepting p-CN substituent in the triplet diradical 7e reduces while the spin-donating... 

Tetralone-8-carboxylic acid, an example of a cis unsaturated 1,4-dicarbonyl compound, cyclizes with phenylhydrazine to give 2,7,8,9-tetrahydro-2-phenyl-3//-benzo[<7e]cinnolin-3-one in over 90% yield <81S59>. 

Mallakpour et al. [24, 35-41] have investigated the synthesis of PAs [PA-(7A-7E. j)] (Figure 5.13) from chiral diacids 5-(4-methyl-2-phthalimidylpentanoylamino) isophthalic acid, (2S)-5-(3-phenyl-2-phthalimidyl pro-panoylamino)isophthalic acid, 5-(3-methyl-2-phthalimidyl pentanoyl amino) isophthalic acid, (2S)-5-[4-(4-methyl-2-phthalimidylpentanoyl-amino) benzoyl amino] isophthalic acid and 5-[3-methyl-2-(l,8-naphthalimidyl)-butanoylamino] isophthalic acid with several aromatic and... 

In the spectrum of nitroxide 7g the assignment of the upheld signals is made from the same considerations as in the case of nitroxide 7e. In the spectrum of nitroxide 7g, in contrast to that of nitroxide 37c, the signals due to all the hve protons of the phenyl group are manifest. 

The shifts of the signals caused by methyl groups in positions 2 and 5 are substantially dependent on the structure of the radical. In all spectra signals are observed corresponding to constant —0.22 Oe. Replacement of one of the methyl groups in position 5 by the phenyl residue causes an increase of constant for another methyl group. For nitroxide 7e an increase of constant takes place as well. In the case of nitroxide 37c and 37c(D), nonequivalence of methyl groups in positions 2 and 5 is also... 

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