Di alkylation

On acetylation it gives acetanilide. Nitrated with some decomposition to a mixture of 2-and 4-nitroanilines. It is basic and gives water-soluble salts with mineral acids. Heating aniline sulphate at 190 C gives sulphanilic add. When heated with alkyl chlorides or aliphatic alcohols mono- and di-alkyl derivatives are obtained, e.g. dimethylaniline. Treatment with trichloroethylene gives phenylglycine. With glycerol and sulphuric acid (Skraup s reaction) quinoline is obtained, while quinaldine can be prepared by the reaction between aniline, paraldehyde and hydrochloric acid. 

In brief, suitable hydrolysis of ethyl acetoacetate derivatives will give mono-or di-alkyl substituted acetones or acetic acids. Tri-substituted acetones or acetic acids cannot be obtained moreover, the di-substituted acetones must... 

Di-alkyl ethers of ethylene glycol, ROCHjCHjOR. The dimethyl ether, b.p. 85°/760 mm., is miscible with water, is a good solvent for organic compounds, and is an excellent inert reaction medium. The diethyl ether (diethyl cdloaolve), b.p. 121-57760 mm., is partially miscible with water (21 per cent, at 20°). 

The mono-alkyl C-substituted derivatives of ethyl acetoacetate upon treatment with sodium ethoxide and another molecule of alkyl halide afford the di-alkyl C-substituted products... 

V-Alkylaniline and /V,/V-di alkyl aniline hydrochlorides can be rearranged to C-alkyl anilines by heating the salts to 200—300°C. In this reaction, known as the Hofmann-Martius rearrangement, the alkyl group preferentially migrates to the para position. If this position is occupied, the ortho position is alkylated. 

Organosulfur Adsorbates on Metal and Semiconductor Surfaces. Sulfur compounds (qv) and selenium compounds (qv) have a strong affinity for transition metal surfaces (206—211). The number of reported surface-active organosulfur compounds that form monolayers on gold includes di- -alkyl sulfide (212,213), di- -alkyl disulfides (108), thiophenols (214,215), mercaptopyridines (216), mercaptoanilines (217), thiophenes (217), cysteines (218,219), xanthates (220), thiocarbaminates (220), thiocarbamates (221), thioureas (222), mercaptoimidazoles (223—225), and alkaneselenoles (226) (Fig. 11). However, the most studied, and probably most understood, SAM is that of alkanethiolates on Au(lll) surfaces. 

Chemisorption of alkanethiols as well as of di- -alkyl disulfides on clean gold gives indistinguishable monolayers (251) probably forming the Au(l) thiolate species. A simple oxidative addition of the S—S bond to the gold surface is possibly the mechanism in the formation of SAMs from disulfides ... 

Titanium Phosphorous Containing Chelates. The reaction of a mixture of mono (alkyl) diacid orthophosphate, di(alkyl)monoacid orthophosphate, and TiCl in a high boiling hydrocarbon solvent such as heptane, with nitrogen-assisted evolution of Hberated HCl, gives a mixture of titanium tetra(mixed alkylphosphate)esters, (H0)(R0)0=P0) Ti(0P=0(0R)2)4 in heptane solution (100). A similar mixture can be prepared by the addition of two moles of P2O5 to mole of TiCl in the presence of six moles of alcohol ... 

Direct reaction with alcohols gives mixed mono-and di-alkyl phosphoric acids by cleavage of the P-O-P bonds ... 

Reaction of the anion derived from the tosyl imide of l,3,S-trithiane with alkyl iodides gives a mixture of the mono- and di- alkylated products, in which anti stereochemistry predominates. The analogous 1,3-dithiane derivative is only monoalkylated <96JCS(P1)313>. 

In addition to the HWE reactions leading to asymmetric vinyHc sulfoxides (not reviewed here), new recent appHcations of enantiopuxe a-sulfinylphospho-nates, such as their use as precursors of optically active di-alkyl or arylalkyl sulfoxides and also of 1 -sulfinyl-phosphonocyclopropanes, increases again their synthetic potential. 

Lindblom and Blander (1980) have given a number of examples of relevance in the pharmaceutical industry. These include C-alkylations, 0-alkylations, and A-alkylations. The C-alkylation of phenylacetonitrile, (mono- and di-) alkylation of benzylpenicillin with a-chlorodiethyl carbonate (where the acid part and the halide part in the esterification would have degraded quickly under normal conditions adopted for the reaction), A-alkylation of purines and adenine, etc. are discussed at some length and the supremacy of PTC is clearly shown. 

Some mechanisms of radical-initiated migration copolymerization of di-alkyl(diphenyl)stannanes with non-conjugated epoxyalkadienes such as 4,4-epoxy-l,7-heptadiene (I) and 3-glycidyl-oxy-l,6-hexadiene (II) have been discussed 98). 

In contrast to the above-mentioned organotin epoxide monomers, di-alkyl(diphenyl)allyl-2,3-epoxypropylstannanes with the general formula R... 

The most common hydrophobes used as the basis for surfactants are those containing eight to eighteen carbon atoms, such as those listed as carboxylates in Table 9.1. Some hydrophobes are aromatic (benzene or naphthalene) moieties, often containing lower alkyl substituents dodecylbenzene (9.1) is a common example. Alkyl-substituted toluenes, xylenes and phenols, and mono- and di-alkylated naphthalenes (9.2 and 9.3), are also used. 

The oxidation of thiophene and its derivatives with H202 was studied using a Ti-Beta molecular sieve. The oxidation product is very dependent from the aromaticity of model compounds. The thiophene oxidation product was mostly sulfates and the benzothiophene oxidation product was benzothiophene sulfone. Oxidation of mono and di-alkyl thiophenes also produced sulfates and sulfones. The diffusivity and aromaticity of the relevant sulfur compounds, intermediates and stable product, as well as the proposed new mechanism of oxidation will be discussed. This proposed new reaction pathway is different from current literature, which reports the formation of sulfones as a stable oxidation product. 

Reaction of nitrosothioureas with alkylamines gives TV-mono- or di-alkyl substituted thioureas (Scheme 53).135... 

Electrodes with liquid ion-exchange membranes are typified by a calcium-sensitive electrode (Figure 6.4). The membrane-liquid consists of the calcium form of a di-alkyl phosphoric acid, [(RO)2POO ] 2Ca2+, which is prepared by repeated treatment of the acid with a calcium salt. The internal solution is calcium chloride and the membrane potential, which is determined by the extent of ion-exchange reactions at the interfaces between the membrane and the internal and sample solutions, is given by... 

The alkylation reaction is initiated by the activation of the alkene. With liquid acids, the alkene forms the corresponding ester. This reaction follows Markovnikov s rule, so that the acid is added to the most highly substituted carbon atom. With H2S04, mono- and di-alkyl sulfates are produced, and with HF alkyl fluorides are produced. Triflic acid (CF3S020H) behaves in the same way and forms alkyl triflates (24). These esters are stable at low temperatures and low acid/hydrocarbon ratios. With a large excess of acid, the esters may also be stabilized in the form of free carbenium ions and anions (Reaction (1)). 

Chapman, N. B., Clarke, K.., and Hughes, H. (1965) Synthesis of some 5-substituted-2-meth-yltryptamines and their N-mono and di-alkyl derivatives. J. Chem. Soc., 1424-1428. 

Alkylarylether derivatives—alkylarylether sulfates, -sulfonates, -phosphates and di-alkyl arylether-carboxylates... 

While APEO cannot be ionised successfully under negative conditions and consequently for identification MS-MS(—) is not informative, the identification of all anionic APEO derivatives is possible in the negative ionisation mode. For some derivatives, negative as well as positive ionisation can be applied. The loss of the anionic moiety, however, must be taken into account if ionisation is performed in the positive mode. Di-NPEC surfactant homologues submitted to negative CID resulted in the prominent di-alkyl-phenolate ion at m/z 345 (Fig. 2.11.18(a) as shown with the homologue m/z 799 under CID conditions). Therefore, the application of the parent ion scan of m/z 345 in the negative ESI and APCI-FIA-MS-MS mode is very specific for the detection of all anionic derivatives of di-NPEO comparable in... 

Tetralone is readily mono- or di-alkylated at the 1-position to the exclusion of O-alky lation with a range of alkylating agents under liquiddiquid two-phase conditions without an added solvent [24], Similarly, it has been reported that anthrone undergoes mono- and di-C-alky lation at the 10-position with propargyl and allyl halides to the almost complete exclusion of O-alkylation [25]. It has been claimed that methyl-ation yields 9-methoxyanthracene [26],... 

C-Alkylation of 2-oxazolin-5-ones under catalysed mildly basic conditions provides a convenient route to a-branched a-amino acids (50-80%) [126]. Similarly, A-alkyloxindoles are mono- and di-alkylated at the 3-position [127], For other examples of the alkylation of heteroaryl systems, see Chapter 5. 

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