Biphenyl, 4-carboxy

Analog wird 6,6 -Dinitro-2 -formyl-2-carboxy-formyl-biphenyl cyclisiert ... 

Dimethylamino-methyl)-2-hydroxymethyl-aus 2 -Carboxy-2-(dimethylaminocarbonyl)-biphenyl und Lithiumalanat 165 2,2 -Dinitro- 474, 476, 695 6,6 -Dinitro-2,2 -bis-[chlorcarbonyl]- 188 2,2 -Dinitro-4,4 -bis-[diathylamino]- 695 4,4 -Dinitro-2,2 -bis-rhydroxymethyl]- 213 6,6 -Dinitro-2,2 -bis-[hydroxymethyl]- 188 2,2 -Dinitro-4,4 -diamino- 695 6,6 -Dinitro-2,2 -diformyl- 694 4,4 -Dinitro-2,2 -dimethoxycarbonyl- 213 2,2 -Dinitro-4,4 -dimethyl- 695 6,6 -Dinitro-2 -formyl-2-carboxy- 694 2,2 -Dinitroso- 476 -4-hydroxamsaure-chlorid 537 4-(a-Hydroxy-benzyl)- 542 Methoxy- 678 2-Methyl- 556 Nitro- 672, 678 4-Nitro- 687... 

Diazotiertes 4-Fluor-anilin reagiert mit Salicylsaurc problemlos zu 3-Carboxy-4 -fluor-4-hydroxy-azobenzol (75% Schmp. 218-220°), das sich mit Tris-[triphenylphosphan]-rhodiumchlorid zum entziindungshemmenden 3-Carboxy-4-fluor-4-hydroxy-biphenyl zersetzen laflt1 ... 

Instead of checking the second stress-optical relation, viz. eq. (1.6), Philippoff preferred to use eq. (1.3), assuming % = %. That this assumption is justified, can be seen in the same Fig. 1.4, In this figure also the extinction angle is plotted against the shear stress. Orientation angles calculated with the aid of eq. (1.3), fit rather well on the extinction angle curve. The normal stress difference (pn — p22) has been measured in the way explained in the previous section. Similar results were published later by the same author for solution of carboxy methyl celluose in water (33) and for S 111 in Aroclor (34) a chlorinated biphenyl. 

S)-N-(l-Carboxy-2-methyl-prop-l-yl)-N-pentanoyl-N-[2 -(lH-tetrazol-5-yl)biphenyl-4-ylmethyl]-amine. The product can be prepared starting from 1.40 g of N-valeryl-N-[(2 -cyanobiphenyl-4-yl)methyl]-(L)-valine methyl ester and 2.25 g of tributyltin azide with subsequent flash chromatography melting interval 105°-115°C (from ethyl acetate). 

It has been demonstrated that the presence of chlorine or bromine in the nucleus facilitates replacement of the diazo group by hydrogen little or no ether formation occurs.26 Apparently iodine also favors the redudng action of alcohols, but this point has not been investigated carefully.26 27 No attempts to deaminate fluorinated amines are recorded. Representative of the effitiency with which ethanol reduces diazonium salts derived from halogenated amines are the deaminations of m-chloroaniline 26 (87% yield), of 2-bromo-4-methylaniline 28 (67% yield), of 2,4,6-tribfomoaniline 29 (ca. 80% yield), and of 2-carboxy-4-iodoaniline30 (ca. 45% yield) in the biphenyl series the deamination of VIII in 53% yield 31 may be dted. 

Muth et al. studied the hydrogenation and cyclization of 2-nitro-2 -carboxy-biphenyl and its carboxy derivatives (22a-22d) over platinum oxide in ethanol (Scheme 9.13).154 IV-Hydroxyphenanthridone (25) was considered to result from the cyclization at the hydroxylamino compound 23, and phenanthridone (26) to result from the amino compound 24 and not via 25, since 25 did not undergo the reduction to yield phenanthridone under the conditions of the reaction. 

Optical activity can also be induced on achiral azobenzene units when they are incorporated into the polymer main chains through covalent bonding to chiral subunits (34-37 in Fig. 14) [88-92]. Axially chiral amino- or carboxy-substituted biphenyl and binaphthyl and tartaric acid derivatives were used as the optically... 

Biphenyl 6 -Carboxy-2,2, 4,4, 6-pentanitro- E16d, 287 (Nitrie-rung)... 

Carbazol 3-Carboxy-2-hydroxy-VI/lc, 1087 (Carboxylier.) VIII, 374 (Carboxylier.) Carbazol-l,4-chinon 6-Hydroxy-9-methyl- E6a, 949 (H3C —NH2 + Biphenyl-2,5 2, 5 -bis-chinon) Ethan l,2-Dioxo-l-(4-hydroxy-phenyl)-2-(3-pyridyl)- VII/2a, 755 2H-(Naphtho]2,3-e -l,3-oxazin) ... 

Azulen 3-Ethoxycarbonyl-2-hydroxy-1 -nitroso- V/2c, 298 Biphenyl 4-Hydroxy-4 -methoxy-3-nitro- E16d, 301 (Nitrierung) Naphthalin 3-Carboxy-2-(carboxymethyi-amino)- -Dikaiium-Salz E6b/1, 653 (NH2 - NH-COOH)... 

Biphenyls containing four large groups in the ortho positions cannot freely rotate about the central bond because of steric hindrance. For example, the activation energy (rotational barrier) for the enantiomerization process was determined, AG = 21.8 0.1 kcal mol , for the chiral 2-carboxy-2 -methoxy-6-nitrobiphenyl. In such compounds, the two rings are in perpendicular planes. If either ring is symmetrically substituted, the molecule has a plane of symmetry. For example, consider the biaryls ... 

The HF-SbFs system works well in the Gattermann-Koch formylatlon of arenes and the Koch carbonylation of alkanes [54]. For instance, biphenyl is diformylated in HF-SbFs-CO to afford 4,4 -diformylbiphenyl as a major isomer (Scheme 14.20). The carbonylation of alkanes with C5-C9 carbon atoms in the HF-SbFs-CO system affords mixtures of C3-C8 carboxylic acids after hydrolysis of the generated secondary carbenium ions [55]. Successive treatment of methylcyclopentane with CO in HF-SbF and with water produces cyclohexanecarboxylic acid as a major product (Scheme 14.21) [56]. It seems that a tertiary methylcyclopentyl cation readily isomerizes to the more stable cyclohexyl cation before being trapped by CO. Bicyclic a, -unsaturated ketones are functionahzed by HF-SbF or FSOsH-SbFs under a CO atmosphere to give saturated keto esters after methanolysis (Scheme 14.22) [57]. Alcohols with short carbon chains also react with CO in HF-SbFs to give the corresponding methyl esters [58]. y-Butyrolactones are carboxy-lated under the same conditions to afford 1,5-dicarboxyhc acids [59]. 

OQ-cn Cl Ethanol, 10 N NaOH Riickfl. 6-36 4-Carboxy-3-chlor-biphenyl 81-90 438... 

Carboxy-l, 10-biphenyl)-2-yl]pyrrole- 2- carboxylic acid (S)-l -Phenylethanamine (09CHI905)... 

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