Bromopropylate

By-products include propylene dibromide, bis-(bromopropyl) ether, propylene glycol, and propionic acid. Bromide losses are to the brominated organics and bromate formation. Current efficiency is a function of ceU design and losses to bromate. Energy consumption decreases with an increase in electrolyte concentration and a decrease in current density. Space—time yield increases with current density. See Table 5 for performance data (see... 

V-(3-Bromopropyl)phthalimide [5460-29-7] M 268.1, m 72-74 , 74 . Place in a Soxhlet and extract with Et20, whereby the bis-phthalimido impurity is not extracted. Evaporate the Et20 and recryst from EtOH or aqueous EtOH or pet ether. [Chem Ber 21 2669 1888 Justus Liebigs Ann Chem 614 83 1958 Can J Chem n 1060 7955.]... 

Craig s synthesis of nicotine (V to VII, p. 42) proceeds via nomicotine. Nicotinic acid nitrile reacts with the Grignard reagent derived from ethyl y-bromopropyl ether to give 3-pyridyl-y-ethoxypropyl ketone (V). This yields an oily oxime (VI) reducible to a-(3-pyridyl)-a-amino-8-ethoxy-w-butane (VII), which with 48 per cent, hydrobromic acid at 130-3° gives womicotine, and this on methylation yields dZ-nicotine. 

The formation of bicyclic imines (263,264) from piperidine enamines and y-bromopropyl amines may appear at first sight to be a simple extension of the reactions of enamines with alkyl halides. However, evidence has been found that the products are formed by an initial enamine exchange, followed by an intramolecular enamine alkylation. Thus y-bromodiethylamino-propane does not react with piperidinocyclohexene under conditions suitable for the corresponding primary amine. Furthermore, the enamine of cyclopentanone, but not that of cyclohexanone, requires a secondary rather than primary y-bromopropylamine, presumably because of the less favorable imine to enamine conversion in this instance. 

The intramolecular cyclization of l-(4-bromobutyl)-3-methoxycarbonyl-l,4,5, 6-tetrahydropyridine (140) and l-(3-bromopropyl)-3-methoxycarbonyl-l,4,5,6-tetrahydropyridine (143) (89T5269) resulted in the synthesis of quinolizidine ring system 141 and indolizidine ring system 144 in 43% and 72% yields along with the reduced tetrahydropyridines 142 and 145 in 21% and 8% yields, respectively. All the cyclized products appeared to be (ran.s-fused indolizidines or quinolizidines. The (ran.s -fused simple indolizidines are known to be some 2.4 kcal mol more stable than the d.s-fused isomers (68TL6191). In the and-isomer the methoxycarbonyl substituent occupies an equatorial position. 

A similar reaction of y-bromopropyl derivatives under the influence of silver nitrate was described by Kohn as early as 1904. The 3-hydroxyketone formed from chloral and acetophenone can react with a chlorocarbamate to yield a pseudourethane which is probably a 4-hydroxy-2-0X0 tetrahydro-l,3-oxazine. ... 

An interesting method of preparing 2-iminotetrahydro-l,3-oxazine derivatives (30) consists in cyclizing A -butyl-A -(y-bromopropyl)-cyanamide. ... 

Dihydro-l,3-4//-oxazines (32) are among the best known 1,3-oxazines. Their preparation was first described by Gabriel and Elfeldt in 1891. The reaction consisted in benzoylation of y-bromopropyl-amine in the presence of sodium hydroxide by an intermediate formation of A"-benzoyl-y-bromopropylamine (31). The cyclization of the... 

Some rather unexpected formations of 5,6-dihydro-l,3-4i/-oxazines have also been noted, e.g., reaction of y-bromopropyl iminobenzoate with hydrogen sulfide, which yielded in addition to the main product (thiobenzoate) small amounts of (35) ... 

Side-chain bromination at the benzylic position occurs when an alkylbenzene is treated with /V-bromosuccinimide (NBS). For example, propylbenzene gives (l-bromopropyl)benzene in 97% yield on reaction tvith NBS in the presence of benzoyl peroxide, (PhC02)2f as a radical initiator. Bromination occurs exclusively in the benzylic position and does not give a mixture of products. 

Addition of HBr to 1-phenylpropene yields only (l-bromopropyl)benzene. Propose a mechanism for the reaction, and explain why none of the other regioisoiner is produced. 

This type of ring system appears as salt 215. Thus, the reaction of azauracils 213 with dibromopropane at 78-85°C gave bromopropyl derivatives 214, whereas at 110-120°C the cyclized salts 215 were formed (82MI7, 82MI8) (Scheme 47). 

Reduction of iV-(3-bromopropyl) imines gives a bromo-amine in situ, which cyclizes to the aziridine. Five-membered ring amines (pyrrolidines) can be prepared from alkenyl amines via treatment with N-chlorosuccinimide (NCS) and then BusSnH. " Internal addition of amine to allylic acetates, catalyzed by Pd(PPh3)4, leads to cyclic products via a Sn2 reaction. Acyclic amines can be prepared by a closely related reaction using palladium catalysts. Three-membered cyclic amines (aziridines)... 

C 5H2 BrN2) see Ethoheptazine ( )-2-(3-bromopropyl)-4-(l-ethoxyethoxy)-3,4-dihydro-2//-thieno[3,2-e]-l,2-thiazine 1,1-dioxide (C 2H2()BrN04S2 165116-91-6) see Brinzolamide... 

C jH 7Br 3436-04-2) see Amitriptyline Amitriptylinoxide Nortriptyline Al-(3-bromopropyl)phthalimide (C, H,oBrN02 5460-29-7) see Roxatidine acetate... 

This approach makes use of bromopropyl phosphine 17 as a key synthon obtained via the reduction of 3-bromopropyl phosphonate with dichloroaluminum hydride [10]. Reaction of bromopropyl phosphine 17 with the dianion of 6,8-dithiooctanoic acid produced the -COOH functionalized P2S2-primary bisphosphine framework 18 in > 80% yields (Scheme 7) [10]. 

Treating 2 -ani lino-6 -[/V-ethyl-/V-(3-methoxypropyl)ami no]-3 -methyl-fluoran (88) with 48% hydrobromic acid in the presence of concentrated sulfuric acid at 110-11 5 °C gives 2 -anilino-6 -[/V-(3 -bromopropyl)-7V-ethylamino]-3 -methylfluoran (89)70 in excellent yield (Eq. 10). 

Preparation of 2 -Anilino-6 - [N- (3-bromopropyl) -N-ethylaminoJ-3 -methylfluoran (89). To a mixture of 2 -anilino-6 -[/V-ethyl-Af-( 3-methoxy-propyl)amino]-3 -methylfluoran (0.1 mol) and 48% hydrobromic acid (150 ml) was added dropwise concentrated sulfuric acid (20 ml) with vigorous stirring. Then, the resulting mixture was stirred at 110-115 °C for 1 h, poured into ice water (1000ml), and made alkaline by aqueous sodium hydroxide. The pale violet precipitate was filtered off, and recrystallized from ethyl acetate-isopropanol to give 2 -anilino-6 -[/V-(3-bromopropyl)-,V-ethylamino]-3 -methylfluoran in 96% yield, mp 160-162 °C. 

Bromide appears to be useful in this regard. Table II summarizes our homopolymerization experiments on (2-bromoethyl)oxirane, (3-bromopropyl)oxirane and (4-bromobutyl)oxirane (3a-c) (10-12). 

Figure 2. Conversion versus time for substitution by tetrabutyl-ammonium benzoate on poly(epibromohydrin) (O) poly[(2-bromo-ethyl )oxirane] (0) poly[(3-bromopropyl )oxirane] (v, , separate runs) and poly [(4-bromo butyl )oxirane] (a, , separate runs).

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