Mides

The in ternal arch itecture of HyperChem back ends is different from that expected to be used by third-party packages. To a third-party agent wishing to interface with HyperChem, HyperChem always acts as a server. Thus a third-party molecular dynamics package w oiild ask HyperChem to send th e coordinates of a mide-cu le rath cr th an HvperCIhem determ in in g on its own that it should send coordinates at the appropriate time. 

A -Bromosuccinimide (prepared by the action of bromine on succinimide at o in the presence of sodium hydroxide) is a valuable specific reagent for brominating olefines in the a-methylene position to the double bond without simultaneously adding bromine to this bond. For example, if A -bromosuccini-mide is represented by (C4H40t)NBr —... 

Method(B). Add3g. (3ml.)ofbenzonitrileto50ml.of lo-volumes hydrogen peroxide in a beaker, stir mechanically and add i ml. of 10% aqueous sodium hydroxide solution. Warm the stirred mixture at 40° until the oily suspension of the nitrile has been completely replaced by the crystalline benzamide (45-60 minutes). Cool the solution until crystallisation of the benzamide is complete, and then filter at the pump and recrystallise as above. One recrystallisation gives the pure benza-mide, m.p. 129-130° yield of purified material, 2-2-5 S ... 

Amine B.P. M.P. Aceta- mide Benz- amlde Benzene- SUlphOD- amlde p-Tolu- enesul- phoD- amlde Benzal Derivative Picrate 3-Nitro- phthal- imide 2 4-Dinitro-phenyl Derivative Formyl Derivative Phenyl thio- urea... 

The addition of N-bromosuccinimide (1.1equiv) to a dichlo-romethane solution containing the alkene (1 equiv) and cyana-mide (4 equiv). The solution was maintained at room temperature (3 days) and then washed with water, dried, and concentrated in vacuo. Treatment of the bromocyanamide [intermediate] with 1% palladium on charcoal in methanol (1h) led to reduction of the for-madine. Addition of base to the reaction mixture (50% aqueous KOH, reflux 6h) followed by extraction with ether gave monoamine. (Yield is 48-64% final amine from alkenes analogous to safrole)... 

Benzyl bromide can be converted into ethylbenzene (731) by the reaction of Me4Sn. The use of HMPA as a solvent is important. Overall inversion of configuration takes place at the chiral center of deuterated benzyl bro-mide[598]. The cyanomethyiation[599] and methoxymethyiation[600] of aromatic rings are carried out by the reaction of cyanomethyltributyltin (732) and methoxymethyltributyltin. 

Because alkyl halides are insoluble m water a mixture of an alkyl halide and water sep arates into two layers When the alkyl halide is a fluoride or chloride it is the upper layer and water is the lower The situation is reversed when the alkyl halide is a bro mide or an iodide In these cases the alkyl halide is the lower layer Polyhalogenation increases the density The compounds CH2CI2 CHCI3 and CCLi for example are all more dense than water... 

Assuming that the rate determining step in the reaction of cyclohexanol with hydrogen bro mide to give cyclohexyl bromide is unimolecular write an equation for this step Use curved arrows to show the flow of electrons... 

How many alkenes would you expect to be formed from each of the following alkyl bro mides under conditions of E2 elimination Identify the alkenes in each case... 

A much more serious drawback to using chiral drugs as racemic mixtures is illustrated by thalidomide briefly employed as a sedative and antinausea drug in Europe during the period 1959-1962 The desired properties are those of (/ ) thalidomide (S) Thalido mide however has a very different spectrum of bio logical activity and was shown to be responsible for over 2000 cases of serious birth defects in children born to women who took it while pregnant... 

Because halides are poorer leaving groups than p toluene sulfonate alkyl p toluene sulfonates can be converted to alkyl halides by 8 2 reactions involving chloride bro mide or iodide as the nucleophile... 

With primary alcohols Ihe nexl slage is an 8 2 reaclion m which Ihe halide ion bro mide for example displaces a molecule of water from Ihe alkyloxonium ion... 

Halogenation Bromine reacts with benzene in the presence of iron(lll) bro mide as a catalyst to give bromobenzene Chlorine reacts similarly in the presence of iron(lll) chloride to give chlorobenzene... 

FIGURE 13 16 The methyl ene protons of ethyl bro mide split the signal of the methyl protons into a triplet... 

Organolithium reagents (Section 14 3) Lithi um metal reacts with organic halides to pro duce organolithium compounds The organic halide may be alkyl alkenyl or aryl Iodides react most and fluorides least readily bro mides are used most often Suitable solvents include hexane diethyl ether and tetrahy drofuran... 

Tola mide. Tola2imide (l-(hexahydro-lJT-a2epin-l-yl)-3-(p-tolysulfonyl)urea), mol wt 311.40, is a white to off-white crystalline powder, ododess or having a slight odor, mp 170—173°C, with a piC of —3.6 at 25°C and 5.68 at 37.5°C. It is very slightly soluble in water, freely soluble in chloroform, soluble in acetone, and slightly soluble in alcohol. The trade name is Tolinase. 

A. L. McKenna, Eatty A.mides, Witco Chemical Corporation, Term., 1982, p. 1. 

Disopyr mide. Disopyramide phosphate, a phenylacetamide analogue, is a racemic mixture. The dmg can be adininistered po or iv and is useful in the treatment of ventricular and supraventricular arrhythmias (1,2). After po administration, absorption is rapid and nearly complete (83%). Binding to plasma protein is concentration-dependent (35—95%), but at therapeutic concentrations of 2—4 lg/mL, about 50% is protein-bound. Peak plasma concentrations are achieved in 0.5—3 h. The dmg is metabolized in the fiver to a mono-AJ-dealkylated product that has antiarrhythmic activity. The elimination half-life of the dmg is 4—10 h. About 80% of the dose is excreted by the kidneys, 50% is unchanged and 50% as metabolites 15% is excreted into the bile (1,2). 

Oxa.mide. Oxamide [471 6-5] is a nonhygroscopic single compound. It has a molecular weight of 88.08, a nitrogen content of 31.8%, and is a white crystalline soHd with very limited solubiUty in water. Table 4 Hsts select physical properties. 

The ability to convert a protective group to another functional group directly without first performing a deprotection is a potentially valuable transformation. Silyl-protected alcohols have been converted directly to aldehydes, ketones, bro-mides, acetates, and ethers without first liberating the alcohol in a prior deprotection step. 

Another recently discovered form of epitaxy is graphoepitaxy (Geis et al. 1979). Here a non-crystalline substrate (often the heat-resistant polymer polyi-mide, with or without a very thin metallic coating) is scored with grooves or pyramidal depressions the crystalline film deposited on such a substrate can have a sharp texture induced by the geometrical patterns. More recently, this has been tried out as an inexpensive way (because there is no need for a monocrystalline substrate) of preparing oriented ZnS films for electroluminescent devices (Kanata et al. 1988). 

The mtroducuon of a tnfluoromethanethio group into an aromatic nng has a synthetic importance The reaction of tnfluoromethanethio copper with aryl bro mides and iodides provides a convenient route to the synthesis of aryltn fluoromethane sulfides The reaction is not sensitive to the type of substituents or the aromahc nucleus Selectivity can be achieved accordmg to the type of halogen or the aromatic rmg, because iodides react at lower temperatures than bromides, whereas chlondes do not react [f J] (equation 12) (Table 5)... 

Vinylogous forma mides have been obtained by double Vilsmeier reactions of methyl ketones (53,54), 4-methylpyridine (53,54), and olefinic (55) compounds. The dienamine intermediates were demonstrated in the latter cases. 

The reactions of enamines with positively activated olefins have been extended to arylations with />-quinones (350,362-369) and quinone sulfoni-mides (365-368,370). Thus a new pathway for the facile formation of benzofurans and indoles became available. 

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