Diphenic acid derivative

To obtain additional proof for the absolute configuration of the flavomannin group, we tried to carry out a synthesis starting with a diphenic acid derivative of known absolute configuration (Scheme 9). 

An interesting coupling reaction with the diazonium salt derived from anthranilic acid leads to an excellent method for the preparation of diphenic acid. The reaction occurs with cuprous salts in ammoniacal solution y /COOH 2JJC1 y yCOOIl 2Cu+... 

CD and ORD measurements are a useful tool in studying configuration and conformation. The configuration of optically active 4,4 -dicarboxy-2,2, 5,5 -tetramethyl-3,3 -biselenienyl (1, X = Se) relative to its thiophene analog (1, X = S), was determined by reducing both to the corresponding 4,4 -dihydroxymethyl derivatives (2), which could be related to each other by the quasi-racemate method and by circular dichroism studies.15 Compounds 1 have also been related to 3,3, 6,6 -tetramethyl-2,2 -diphenic acid (3), and it was found that the levorotatory form of 1 (X = Se, S) and the dextrorotatory form of 3 have the -configuration.16... 

The heterocyclic acylphosphines (52) and (53) have been prepared by the reaction of phenylbis(trimethylsilyl)phosphine with the acid chlorides derived from phthalic and diphenic acids. The reaction of 2,3-dichloromaleic anhydride or thioanhydride with phenylbis(trimethylsilyl)phosphine gives derivatives of the 1,4-dihydro-p-diphosphorin system (54).45... 

Fig. 5.26. Metabolism of the piperidine ring according to the mechanism in Fig. 5.23. Diphen-idol (5.97) and DN-9893 (5.73) yield both amino acid and lactam metabolites [177], Phencyclidine (5.98) yields only the amino acid derivative steric hindrance at the N-atom appears to impede formation of the lactam metabolite [190].

Alcohols, prior to the separation by means of paper or thin layer chromatography, must be converted into suitable derivatives, mostly into 3,5-dinitrobenzoic acid esters or into the acid semiesters of 3-nitrophthalic acid or diphenic acid. The direct re-esterification of ester plasticizers with 3,5-dinitrobenzoic acid is applicable to plasticizer analysis (7). 

The above procedure is derived from the work of Atkinson and Lawler 6 but employs a more suitable reducing agent than that7 previously used to convert diazotized anthranilic acid to diphenic acid. The product can be resolved into its optically active forms,6 which are stable to racemization. 

Diphenic acid (17) and its ester as well as ci s-hexahydro-2,2 -diphenic acid (18) are all hydrogenated largely to give cw- yn-aT-perhydro derivatives over platinum oxide in acetic acid, in the same stereochemical manner as do its anhydride and the phenanthrene derivatives related to it (Scheme 11.12).198,199 Linstead et al. explained the results on the assumption that the diphenic acid or its ester are hydrogenated in the coiled form (17a), rather than in the zigzag form (17b), which is expected to yield the product with a cis-anti-cis configuration.62... 

Diorganotin(iv) derivatives of diphenic acid 233 were prepared by reaction of dialkyltin(iv) oxide with diphenic acid and its sodium salt in 1 1 molar ratio (Figure 9). Structure of these compounds was confirmed by IR, H, and 13C... 

The bis(diazoketone) (N.CHCOC-H,), derived from diphenic acid, forms the... 

In the acid fractionation of the low-boiling portion, b.p. 120-140yi mm., of crude nicotine, the third fraction contains optically impure Z-anatabine which is purified by crystallization of the perchlorate. The mother liquor from the perchlorate (403) contains an optically inactive base which on dehydration produces 3, 2-dipyridyl, while oxidation of its benzoyl derivative gives rise to hippuric acid. Since the base has been resolved with Z-6,6 -dinitro-2,2 -diphenic acid to Z-anatabine it is dZ-anatabine. 

Another derivative of phenanthrene is 2,2 -diphenic acid, which can be used in the production of polyesters and alkyd resins. 

Most of the congeners of thalmine, C20H23O3N (see Volume V, p. 325), are aporphines but this alkaloid proved to be the first of a new structural type. There are two methoxyls in the molecule and the third oxygen is present as hydroxyl. Acetylation yields a neutral 0,V-diacetyl derivative and Hofmann degradation yields in two stages a compound formulated as LXXXVI (mp 212°). This on oxidation generates 5,6 -dimethoxydiphenic acid which is also obtained by oxidation of the alkaloid. Reduction of LXXXVI leads to the formation of a dihydro derivative (mp 173°) which on oxidation yields the diphenic acid as well as propionic acid. The proposed structure (LXXXV) accounts for these reactions but equally satisfactory would be one in which the piperidine nucleus is inverted with the nitrogen at the top in the formula (231). 

New benchrotrene derivatives have been prepared by reactions of [Cr(CO)s], etc., with oestrone and related steroids, phenalene, 2,6,15,19-tetrathia-[7.7]paracyclophane, PhjAs, and diphenic acid and related compounds. Ring-substituted derivatives of [( benzaldehyde)Cr(CO)3] have been resolved into enantiomeric forms. Reactions of carbene complexes of the type [(OQs-CrC(OMe)Ar] with alkynes have afforded derivatives of [(jy -naphthalene)-Cr(CO>3] (see Vol. 8, refs. 393, 394). 

The second promising new type of polymer was made from 2,2 -diphenylethynyl-4,4 -diphenic acid units which cure on heating to give phenylbenzanthracene units in the polymer chain. The new polymer also belongs to the polyaromatic ether-keto-sulfone series. This polymer was prepared from dimethyl 4,4 -diphenate by direct iodination in sulfuric acid with a silver sulfate catalyst to give the 2,2 -diiodo derivative in 80-85% yield. When hydrolized to the acid it could be converted to the acid chloride on treatihent with oxalyl chloride in pyridine solution. 

Further studies on the effect of chiral elements showed that ketone 10 derived from 6,6 -dinitro-2,2 -diphenic acid gave ee values similar to ketone 9 (Scheme 3.10)... 

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