5- Bromo-2-methyl-1-pentene

C6H10O3 2,2-dimethyl-1,3-dioxolane-4-carboxaldehyde 5736-03-8 459.55 40.012 2 7983 C6H11Br 5-bromo-2-methyl-2-pentene 2270-59-9 426.15 43.023 1,2... 

Trisubstituted olefins. The oxirane (l)2 is converted into (2a), (E)-5-bromo-2-methyl-2-pentene-l-ol, in 81 % yield (pure) when treated with 48% hydrobromic acid at 0° for 1 hr. Alternatively, (1) is transformed into (2b) by treatment with sodium... 

It has been shown that halogen-substituted alkenes can participate in the metathesis reaction, e.g. 5-bromo-l-pentene reacts with 2-pentene 11). A very interesting reaction is the conversion of methyl-9-octa-decenoate into 9-octadecene and dimethyl-9-octadecenedioate 12) ... 

C5H9Br trans-1 -bromo-1 -pentene 31849-76-0 388.15 34.370 1.2 5046 C5H9CI 3-chloro-3-methyl-1 -butene 2190-48-9 353.15 29.477 1.2... 

C5H9Br 2-bromo-1-pentene 31844-95-8 381.15 33.538 1,2 5047 C5H9CI 4-chloro-3-methyl-1 -butene 10524-01-3 365.15 31.098 1,2... 

C5H9Br 3-bromo-1-pentene 53045-71-9 383.15 33.681 1.2 5048 C5H9CI 1 -chloro-2-methyl-cis-2-butene 23009-74-7 381.15 32.491 1,2... 

C5H9Br 4-bromo-1 -pentene 31950-56-8 384.15 33.773 1,2 5049 C5H9CI 1 -chloro-2-methyl-trans-2-butene 23009-73-6 378.15 32.223 1.2... 

C5H9Br 5-bromo-1-pentene 1119-51-3 401.15 35.662 1.2 5050 C5H9CI 1 -chloro-3-methyl-2-butene 503-60-6 383.15 32.670 1,2... 

Trans 1-Bromo-2-pentene (2)3 Methyl cyclopropyl carbmol 1 (43 5 g, 0 5 mol) was stirred at room temperature with 48% HBr (200 mL) for 10-15 min After extraction with petroleum ether (40-60°C) and washing the extract with NaHCC>3 solution, the solvent was removed in vacuum... 

In the area of cyclodextrin ethers the -compound has been converted into a set of five tris-Tbdms ethers, all substituted at their various 6-positions, which were separated by hplc and characterized by n.m.r. spectroscopy. Related work applied to y-cyclodextrin gave the various 6,6 -disubstituted ethers. 5-Bromo-l-pentene was used to produce the 2-0-mono-4-pentenyl ether of P-cyclodextrin which was then permethylated and the product was chemically bonded to silica gel to form an efficient hplc stationary phrase for the separation of enantiomers. Peroctyl a-cyclodextrin has been studied as a chiral receptor for the ephedrinium ion. Various octyl ethers of a-, P- and y-cyclodextrin ranging in their substitution from the diethers to completely alkylated products were characterized by electrospray mass spectrometry and n.m.r. methods applied to methylated derivatives. The 2,6-didodecyl derivative of p-cyclodextrin has been used as a potentiometric sensor. In the field of aromatic ethers, naphthyl carboxylate substituents have been bonded at the 6-positions and the products were able to transfer excitation energy to complexed merocyanine held in the cavities of those molecules. These phototransfer processes were extremely efficient.P-Substituted cyclodextrin derivatives with p-allyloxybenzoyl or various benzyl substituents at 0-2 or 0-3 were incorporated by hydrosilylation to give hydromethylpolysiloxane polymers used as chiral phases for chromatographic resolution of enantiomers. Cyclodextrins with complex benzyl-like eth are illustrated in 22 and 23. The latter were prepared as artificial redox enzymes. 

Apart from halogen substituted alkenes, heteroatoms normally deactivate catalytic systems. However the synthetic utility of such reactions has encouraged further research in this field. Chlorine substitution at vinylic positions deactivates the double bond but halogen substituted alkenes in which the double bond is in an position undergo cross metathesis with internal alkenes. For example, 5-bromo-l-pentene undergoes cross metathesis with 2-pentene. Unsaturated compounds containing ester groups also react, e.g. methyl-9-octadecenoate is converted to 9-octadiene and dimethyl-9-octadecenedioate by the WCl —Sn(CH3)4 catalytic combination [15]. 

When 2-bromo-2-methylpentane is dissolved in DMF, the formation of 2-methyl-1-pentene (A) and 2-methyl-2-pentene (B) occurs. The ratio of alkenes formed is not... 

Pentanal, 5-amino [14049-15-1], 121 Pentane, 1-bromo- [110-53-2], 82 Pentanediotc acid [ 110-94-1 ], 98 3-Pentenoicacid, 4-methyl- [504-85-8], 70 3-Penten-2-ol, 3-bromo-, acetate [14362-79-9], 35... 

Pentenoic acid 4-methyl-, 70 3 Penten 2-ol, 3 bromo, acetate, 35 3-Penten-2-ol, 3-bromo-4-methyl-, acetate,... 

Capillary gas chromatography is conducted with a cross-linked phenyl methyl silicone stationary phase (5%, 25 m x 0.2 mm x 0.5 pm film thickness, injector temp. 225°C, detector temp. 250°C, column temp. 40-200°C, 15°C/min after 1 min initial time). (Z)-2-Bromo-5-(trimethylsilyl)-2-penten-4-ynoic acid ethyl ester is observed to have a retention time of 14.0 min. GC data for bis(trimethylsilyl)butadiyne is as follows retention time 10.0 min, response factor (GC area produced relative to an equimolar quantity of (Z)-2-bromo-5-(trimethylsilyl)-2-penten-4-ynoic acid ethyl ester) 1.29. For (E)-2-[(trimethylsilyl)ethynyl]-5-(trimethylsilyl)-2-penten-4-ynoic acid ethyl ester the retention time is 17.0 min, the response factor 1.19. 

The Pirrung synthesis is notable for its brevity and clever amalgamation of [2 + 2] photocycloaddition and Wagner-Meerwein rearrangement chemistry Enol ether 757 was reacted with the Grignard rea nt from 5-bromo-2-methyl-l-pentene, subjected to acid hydrolysis, and irradiated to generate the tricycle 738. Wittig olefination of this ketone and treatment with p-toluenesulfonic acid provided racemic isocomene. 

S)-1-Phenyl-3-methyl-1-pentene. Freshly distilled benzalde-hyde (53 grams, 0.5 mole) was added slowly (2 hrs) at 0°C to a solution in ethyl ether (400 ml) of a Grignard reagent prepared from ( + )(S)-1-bromo-2-methylbutane [75.5 grams, 0.5 mole) [ ]D25 + 3.968, op 97.2% (20)] and Mg (12 grams). 

The effect of chain length on the catalytic performance was investigated using a series of co-bromo-2-methylalkenes. In all cases the predominant enantiomer produced had the -configuration except for 3-bromo-2-methylpropene oxide, which was predominantly in the S-form due to the priority switch [274], The short propene and butene derivatives were converted quantitatively whereas the longer pentene, hexene and heptene substrates failed to convert completely. Many other functional groups such as carboxylic ester, methoxy, acetoxy and carbonic ester are accepted by the system. The epoxidation fails, however, for 4-hydroxy-2-methyl-l-butene as substrate [270]. 

Three alkenes are possible from 3-bromo-2-methylpentane. Loss of the C-2 proton gives 2-methyl-2-pentene. 

Answer A is an acyclic olefin containing an allylic Br (3 bromo-4-methyl-1 -pentene). 

Bromo-3-methylpentane 3-Methyl-2-pentene 2-Ethyl-l-butene... 

Z )-3-methyl-2-pentene NaN3/NBS dme/h2o (2R, 3R )-2-azido-3-bromo-3- methylpentane 55 34... 

C5H9Br 1 -bromo-cis-2-pentene 7348-78-9 396.15 35.112 1.2 5051 C5H9CI 2-chloro-3-methyl-2-butene 17773-65-8 367.15 31.005 1.2... 

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