F 3-Bromo-l-propene

Allyl 4-toluenesulfonate, 3315 f Allyl vinyl ether, 1904 f 3-Aminopropene, 1254 3-Azidopropene, 1188 f l-Bromo-2-butene, 1548 f 3-Bromo-l-propene, 1153 /V-Chloroallylaminc. 1202 l-Chloro-4-(2-nitrophenyl)-2-butene, 3270 f 3-Chloropropene, 1158 f 3-Cyanopropene, 1465 f Diallylamine, 2450 f Diallyl ether, 2431... 

Allyloxy-2,3-epoxypropane, 2428 iV-Allylthiourea, 1595 f 3-Aminopropene, 1250 3-Azidopropene, 1184 f 3-Bromo-l-propene, 1149 f l-Bromo-2-butene, 1543... 

Of the lower members of this reactive group of compounds, the more lightly substituted are of high flammability and many are classed as peroxidisable and as polymerisable compounds. Individually indexed compounds are f Acrylonitrile, 1104 f 4-Bromo-l-butene, 1544 f 3-Bromo-l-propene, 1149 f l-Bromo-2-butene, 1543 4-Bromocyclopentene, 1878 f Bromoethylene, 0723 f Bromotrifluoroethylene, 0576 f 2-Chloro-1,3-butadiene, 1447 f 3-Chloro-l-butene, 1547... 

Allyl benzene sulfonate, 3155 f Allyl bromide, see 3-Bromo-l-propene, 1153 f Allyl chloride, see 3-Chloropropene, 1158... 

BROMO-l-PROPENE (106-95-6) Forms explosive mixture with air (flash point 30°F/—1°C). Heat and light can cause decomposition with fumes of hydrogen bromide. Violent reaction with strong oxidizers, strong acids. 

Propene passed ca. 7.5 hrs. into a stirred soln. of bromodicyanomethane in methylene chloride with initial removal of oxygen and subsequent irradiation with a high-pressure Hg-lamp crude 3-bromo-l,l-dicyanobutane (Y 90%) boiled 3 hrs. with HCl (d. 1.19), the intermediate crude 4-hydroxy-2-carboxypentanoic acid lactone (5.5 from 9.2 g.) heated 3 hrs. at 145 and distilled 4-hydroxypentanoic acid lactone (Y 78% based on 3-bromo-l,l-dicyanobutane). F. e., also stereospecific ring closure, and from 1,1-dicyanocyclopropanes, s. P. Boldt, W. Thieleche, and J. Etzemuller, B. 102, 4157 (1969). 

The anti addition of diethyl 7V,Ar-dibromophosphoramidates to acyclic and cyclic alkenes was achieved in the presence of boron trifluoride, which makes the ionic dissociation of the N —Br bond more labile94,9s. After reduction of the initial /J,lV-dibromo adducts with sodium bisulfite, the /i-bromo-A -hydrophosphoramides 3 precursor of / -bromo amine hydrochlorides 4 were obtained (Table 4). However, a mixture of diastereomers was obtained from (Z)-l-phenyl-l-propene and (E)- and (Z)-l,2-diphenylethylene. Direct assignment of stereochemistry by H NMR of the phosphoroamidates derived from 2-butenes was not possible. Detailed analysis is, however, possible for the H-NMR spectra of the /J-bromo amine hydrochlorides. As determined by 31P NMR spectroscopy all additions to unsymmetrical aliphatic alkenes were not regiospecific. The /f-bromo amine hydrochlorides were converted to 1,2-diamines95. 

Reductive 1,2-eIimination of chlorine and bromine from adducts of l-bromo-2-chlorocyclo-propene (see Section 5.2.2.1.2.5.) with oxygen and sulfur hetarenes has served in the synthesis of a number of cycloproparenes. This transformation is effected by low-valent titanium together with lithium aluminum hydride or an organolithium compound. Thus, reaction of the adduct 3 of l-bromo-2-chlorocyclopropene and 1,3-diphenylisobenzofuran with tita-nium(III) chloride and lithium aluminum hydride overnight in tetrahydrofuran led to elimination of both halogens together with extrusion of the oxygen and formation of 2,7-diphenyl-l/f-cyclopropa[ ]naphthalene (4) in 72% yield. 

Ci4Hio02r 1,6 8,13-Bis-oxido[14]annulene, 32B, 178 C10O5, 3-Carboethoxyfuro[3,2-f]coumarin, 44B, 291 ClftHiiBrOa, 3-Bromo-4 a,10 a-dihydrospiro(2,5-cyclohexadiene-l,3-cycloocta-as-trioxin)-4-one, 40B, 303 C1flH11NO4, 1-(4-Methylphenyl)-3-(5-nitro-2-furanyl)-2-propen-1-one, 43B, 396... 

A soln. of propionaldehyde in ether or tetrahydrofuran added to 2 moles of ice-cooled l-diethylamino-2-propen-2-ylmagnesium bromide soln. prepared from l-diethylamino-2-bromo-2-propene and Mg in tetrahydrofuran in the presence of a crystal of iodine l-diethylamino-2-methylene-3-pentanol. Y 70%.—The double bond prevents a possible -elimination, and stable Grignard compounds are obtained. F. e. s. J. Ficini, G. Sarrade-Loucheur, and H. Normant, Bl. 1962, 1219. 

A number of dicycloproparenes have been prepared by way of the l-bromo-2-chlorocyclo-propene adducts in moderate to very good yields (Table 10). A special example of this procedure is the synthesis of li/,4/f-dicyclopropa[A,g]naphthalene (18) in 52% yield from the cycloadduct 17 of 1-bromo-2-chlorocyclopropene with 7,7-dichloro-3,4-bis(methylene)bi-cyclo[4.1.0]heptane (16), in which the elimination described in this section is combined with the double elimination of a 1,1-dichlorocyclopropane vide supra). 

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