cas 503-60-6, 1-Chloro-3-methyl-2-butene | Articles data

Articles about 503-60-6Total 37 be found

Article title
Article abstract
Author
Journal number and time
Download

Surface-mediated hydrohalogenation of isoprene: A facile preparation of prenyl halides
The reaction of isoprene with SOCl2 (0.5 mol equiv.) or PBr3 (0.4 mol equiv.) or PI3 (0.4 mol equiv.) in the presence of SiO2 at -10°C produced prenyl chloride (82%), or bromide (70%) or iodide (65%), respectively, in less than 30 min reaction time.
De Mattos, Marcio C. S.,Sanseverino, Antonio Manzolillo
p. 2181 - 2186
(2003)
Read Online

A mild method for the replacement of a hydroxyl group by halogen: 3. the dichotomous behavior of α-haloenamines towards allylic and propargylic alcohols
A study of the deoxyhalogenation of allylic and propargylic alcohols with tetramethyl-α-halo-enamines is reported. Primary allylic and primary and secondary propargylic alcohols gave the corresponding halides in high yields. Secondary allylic and propargylic alcohols yielded the corresponding secondary halides but the reaction also produced some rearranged primary halides (I > Br > Cl). The reactions with tertiary allylic and tertiary propargylic alcohols gave several products and was therefore of little synthetic value. However, the addition of triethylamine to the reaction mixture or the use of lithium alkoxide instead of alcohol brought about a major change of the course of the reaction which led to amides carrying an allyl or an allenyl group at C2. This was shown to result from a Claisen-Eschenmoser rearrangement of an intermediate α-allyloxy- or propargyloxy-enamine.
Munyemana, Fran?ois,Patiny, Luc,Ghosez, Léon
(2021/06/07)

Synthesis method of 5,5,5-trichloro-2-methyl-2-pentene
The invention provides a synthetic method of 5,5,5-trichloro-2-methyl-2-pentene. The synthetic method comprises the following steps: taking 2-methyl-3-butene-2-ol as an initial compound of a reaction;adding a haloid acid into the reaction system, and conducting distilling to obtain an intermediate product 1-halo-3-methyl-2-butene; adding the intermediate product and chloroform into a reaction kettle, conducting stirring at a low temperature, and adding an inorganic base into the system in batches; wherein the reaction temperature is 0-40 DEG C, the reaction time is 2-10 hours, the mass ratioof the 2-methyl-3-butene-2-ol to the haloid acid in the reaction is (0.3-1):1, the weight ratio of the chloroform to the 1-halo-3-methyl-2-butene is (1-10):1, and the weight ratio of the inorganic base to the 1-halo-3-methyl-2-butene is (0.1-2.0):1. The method is high in reaction yield and low in environmental pollution degree, and the corrosion degree of equipment is reduced.
-
Paragraph 0016; 0017; 0019; 0020; 0025; 0026; 0028; 0029

(2019/06/30)

Method for synthesizing methyl heptenone from isopentenyl alcohol
The invention provides a method for synthesizing methyl heptenone from isopentenyl alcohol. The method comprises the following steps: (1) reacting isopentenyl alcohol with concentrated hydrochloric acid in the presence of a catalyst A, splitting phase for the reacting liquid, washing and distilling the organic phase to obtain a chloro mixture of 1-chloro-3-methyl-2-butene and 3-chloro-3-methyl-1-butene; (2) directly condensing the chloro mixture with acetone in the presence of a catalyst B to obtain a single product methyl heptenone. According to the method, isopentenyl alcohol is efficientlychlorinated in the presence of metal inorganic salt functioning as a catalyst and concentrated hydrochloric acid functioning as a chlorinating agent; the chlorinating reaction liquid is split and simply distilled to obtain the chlorinated mixture, operation steps of isomerization, rectification and the like are not required; alkali solution is promoted by using N,N-dimethyl formamide as a condensation solvent, and a phase transfer catalyst is not required to be added, the condensation time is reduced, and the reaction yield is improved.
-
Paragraph 0048-0050; 0055; 0059; 0063; 0067; 0070

(2019/02/04)

Preparation method of 1-chloro-3-methyl-2-butene
The invention discloses a preparation method of 1-chloro-3-methyl-2-butene. The preparation method is characterized by comprising the following steps: adding 3-methyl-2-butene-1-ol into a closed reaction device, and introducing hydrogen chloride gas under the condition of -30 to 25 DEG C for carrying out reaction; after the reaction is finished, separating and removing the water layer to obtain the 1-chloro-3-methyl-2-butene product. The preparation method takes the 3-methyl-2-butene-1-ol and the hydrogen chloride as raw materials, and an organic solvent and a catalyst do not need to be used in a preparation process, so that an aftertreatment process is simplified, the environmental pollution is reduced, and the production efficiency and safety are improved.
-
Paragraph 0012; 0013; 0014; 0115; 0016; 0017; 0018-0021

(2018/03/26)

METHOD OF CONVERTING ALCOHOL TO HALIDE
The present invention relates to a method of converting an alcohol into a corresponding halide. This method comprises reacting the alcohol with an optionally substituted aromatic carboxylic acid halide in presence of an N-substituted formamide to replace a hydroxyl group of the alcohol by a halogen atom. The present invention also relates to a method of converting an alcohol into a corresponding substitution product. The second method comprises: (a) performing the method of the invention of converting an alcohol into the corresponding halide; and (b) reacting the corresponding halide with a nucleophile to convert the halide into the nucleophilic substitution product.
-
Page/Page column 53; 111; 112

(2017/01/02)

α-Selective Allylation of Isatin Imines Using Metallic Barium
The Barbier-type allylation of isatin imines with allylic chlorides was achieved by using metallic barium as the promoter. Various α-allylated 3-amino-2-oxindoles were synthesized from the corresponding allylic chlorides and isatin imines. The double-bond geometry of allylic chlorides was retained throughout the reaction. An arylic bromide or iodide functionality of the products was robust to metalation under the optimum reaction conditions.
Yanagisawa, Akira,Yamafuji, Seiya,Sawae, Toshiki
supporting information
p. 2019 - 2023
(2016/08/09)

Formamides as Lewis Base Catalysts in SNReactions—Efficient Transformation of Alcohols into Chlorides, Amines, and Ethers
A simple formamide catalyst facilitates the efficient transformation of alcohols into alkyl chlorides with benzoyl chloride as the sole reagent. These nucleophilic substitutions proceed through iminium-activated alcohols as intermediates. The novel method, which can be even performed under solvent-free conditions, is distinguished by an excellent functional group tolerance, scalability (>100 g) and waste-balance (E-factor down to 2). Chiral substrates are converted with excellent levels of stereochemical inversion (99 %→≥95 % ee). In a practical one-pot procedure, the primary formed chlorides can be further transformed into amines, azides, ethers, sulfides, and nitriles. The value of the method was demonstrated in straightforward syntheses of the drugs rac-Clopidogrel and S-Fendiline.
Huy, Peter H.,Motsch, Sebastian,Kappler, Sarah M.
supporting information
p. 10145 - 10149
(2016/08/16)

ISOPRENE OLIGOMER, POLYISOPRENE, PROCESSES FOR PRODUCING THESE MATERIALS, RUBBER COMPOSITION, AND PNEUMATIC TIRE
The invention relates to an isoprene oligomer that contains a trans structural moiety and a cis structural moiety, which can be represented by the following formula (1), wherein at least 1 atom or group in the trans structural moiety is replaced by another atom or group. The invention also relates to a polyisoprene, which is biosynthesized using the isoprene oligomer and isopentenyl diphosphate. Further, this invention provides a rubber composition comprising the isoprene oligomer and/or the polyisoprene, and a pneumatic tire, including tire components (e.g., treads and sidewalls) formed from the rubber composition. wherein n represents an integer from 1 to 10; m represents an integer from 1 to 30; and Y represents a hydroxy group, a formyl group, a carboxy group, an ester group, a carbonyl group, or a group represented by the following formula (2):
-
Paragraph 266

(2014/06/25)

Efficient organic transformations mediated by ZrOCl28H 2O in Water
Operationally simple and environmentally benign methods for some organic transformations comprising reductive coupling of sulfonyl chlorides, chemoselective deoxygenation of sulfoxides, and halogenation of alcohols mediated by ZrOCl28H2O/MX in water have been developed.
Jafarpour, Maasoumeh,Rezaeifard, Abdolreza,Heidari, Mahdieh
experimental part
p. 1470 - 1482
(2011/10/05)

TEMPO/HCl/NaNO2 catalyst: A transition-metal-free approach to efficient aerobic oxidation of alcohols to aldehydes and ketones under mild conditions
Hydrochloric acid, a very inexpensive and readily available inorganic acid, has been found to cooperate exquisitely with NaNO2/TEMPO in catalyzing the molecular-oxygen-driven oxidation of a broad range of alcohol substrates to the corresponding aldehydes and ketones. This transition-metal- free catalytic oxidative conversion is novel and represents an interesting alternative route to the corresponding carbonyl compounds to the metal-catalyzed aerobic oxidation of alcohols.The reaction is highly selective with respect to the desired product when carried out at room temperature in air at atmospheric pressure. Notably, the use of very inexpensive NaNO2 and HCl in combination with TEMPO for this highly selective aerobic oxidation of alcohols in air at ambient temperaturemakes the reaction operationally and economically very attractive. The results of mechanistic studies, performed with the aid of electrospray ionization mass spectrometry (ESI-MS), are presented and discussed. TEMPO, TEMPOH, and TEMPO+ were observed in the redox cycle by means of ESI-MS. On the basis of these observations, a mechanism is proposed that may provide an insight into the newly developed aerobic alcohol oxidation.
Wang, Xinliang,Liu, Renhua,Jin, Yu,Liang, Xinmiao
supporting information; experimental part
p. 2679 - 2685
(2009/04/10)

A novel one-pot conversion of allyl alcohols into primary allyl halides mediated by acetyl halide
A new and simple method for the synthesis of the primary allyl chlorides and bromides 9-16 from the secondary or tertiary allyl alcohols 3-8 and acyl halide was developed (Scheme 2, Table 1). Non-commercially available secondary and tertiary allyl alcohols were synthesized from the related ketones and aldehydes via the addition of vinylmagnesium chloride. Mechanistic studies indicate that the alcohols were first acetylated by the acetyl halide and then protonated prior to substitution by the halide, Cl- or Br -, via an 5N2′ reaction, to yield the primary halides (Scheme 5).
Kishali, Nurhan,Polat, M. Fatih,Altundas, Ramazan,Kara, Yunus
p. 67 - 72
(2008/09/17)

EPOTHILONE ANALOGUES
Epothilone analogues include a molecular scaffold which holds at least one segment of epothilone in a predetermined orientation and which rigidities a region between the macrolactone ring and the aromatic side-chain.
-
Page/Page column 25; 2/22

(2008/06/13)

Selective formation of chloroethane by the hydrochlorination of ethene using zinc catalysts
A detailed study of the hydrochlorination of ethene and higher alkenes using ZnCl2/SiO2 and ZnCl2/Al2O3 catalysts is described and discussed. Based on earlier observations that supported gold can be an active catalyst for both ethyne hydrochlorination and oxidation reactions, we initially investigated using supported gold as catalysts for the oxychlorination of ethene. However, we found that oxychlorination did not occur in the presence of oxygen and, furthermore, that the gold acted as a poison/inhibitor during the initial reaction period, with the underlying reaction being ethene hydrochlorination. Supported Zn2+ was found to be a very effective catalyst for this reaction. The hydrochlorination of higher alkenes occurred, with high selectivity to a range of relatively complex chlorinated hydrocarbon products at rates of ca. 10-13 mol/(kgcat h).
Conte, Marco,Davies, Thomas,Carley, Albert F.,Herzing, Andrew A.,Kiely, Christopher J.,Hutchings, Graham J.
p. 23 - 29
(2008/09/17)

Design, total synthesis, and evaluation of novel open-chain epothilone analogues
The design, total synthesis, and biological evaluation of two open-chain analogues of epothilone incorporating the critical C1-C8 fragment and the aromatic side chain held together by a small molecular scaffold have been achieved. Biological evaluation revealed that further restraint between the flexible C1-C8 region and the molecular scaffold may be necessary for potent inhibition of cell proliferation.
Alhamadsheh, Mamoun M.,Hudson, Richard A.,Tillekeratne, L. M. Viranga
p. 685 - 688
(2007/10/03)

Synthesis and application of quinazoline-oxazoline-containing (Quinazox) ligands
(Chemical Equation Presented) A practical synthesis of potentially tridentate P,N,N-ligands containing two stereogenic elements incorporated into the axially chiral Quinazolinap and centrally chiral 2-oxazoline subunits is reported. The application of these novel hybrid ligands in Pd(0)-catalyzed asymmetric allylic alkylation revealed the matched and mismatched diastereomer, dominant stereogenic element, as well as the effect of the oxazoline R substituent on the level of enantioselectivity (ee's up to 81%).
Fekner, Tomasz,Mueller-Bunz, Helge,Guiry, Patrick J.
p. 5109 - 5112
(2007/10/03)

Synthesis of β-ionone
Preparation of β-ionone by a reaction sequence starting from acetone is described.
Vani,Chida,Srinivasan,Chandrasekharam,Singh
p. 219 - 224
(2007/10/03)

Pyrrolidine derivative, anti-ulcer drug, and antibacterial drug
A pyrrolidine derivative or a salt thereof expressed by the following formula 1: STR1 wherein R1 is an alkenyl group; R2 is a lower alkoxy group or a halogen atom; R3 is a lower alkyl group; X is a group expressed by --O-- or --S--; Y is carbon or nitrogen atom; m is an integer of 1 to 3; and n is an integer of 0 to 2. The pyrrolidine derivative has an anti-ulcer effect or an antibacterial activity against Helicobacter pyroli, and has also high safety to be available for prevention or cure of ulcers.
-
(2008/06/13)

Esterification of carboxylic acid salts
Mono- or polycarboxylic acid esters are prepared by reacting a salt of such carboxylic acid with an organic halocompound, e.g., a (cyclo)alkyl, (cyclo)alkenyl, aryl or aralkyl halide, in an aqueous reaction medium, in the presence of a catalytically effective amount of a phase transfer catalyst, for example an onium salt.
-
(2008/06/13)

Process for the preparation of a quinone derivative
Disclosed herein are a quinone derivative represented by the following formula: STR1 wherein E1 and E2 are identical with or different from each other and mean individually a lower alkyl or lower alkoxy group, or may form an aromatic ring together, E3 denotes a lower alkyl group, n stands for 0 or an integer of 1-9, and a linkage ------ is a single or double bond, such as a vitamin K derivative or coenzyme Q derivative; and a process for the preparation of the quinone derivative at a high yield without forming any geometric isomer; as well as a 1,4,4a,8a -tetrahydro-4a α-alkenyl-1α,4α-methanonaphthalene-5,8-dione derivative which is useful as an intermediate for the preparation of the quinone derivative.
-
(2008/06/13)

TRANSITION METHAL-CATALYZED SUBSTITUTION REACTION OF ALLYLIC PHOSPHATES WITH GRIGNARD REAGENTS
SN2-selective Grignard coupling with primary allylic diphenylphosphates was successfully achieved using Ni or Fe catalyst.In sharp contrast, a catalytic amount of CuCN*2LiCl promoted a SN2'-selective coupling reaction.In the presence of the copper catalyst, stereochemically homogeneous γ-disubstituted allyl Grignard reagents reacted at the less substituted allylic terminus (α-position) with an allylic diphenylphosphate selectively without losing the double bond geometry.
Yanagisawa, Akira,Nomura, Nobuyoshi,Yamamoto, Hisashi
p. 6017 - 6028
(2007/10/02)

Cyclization of farnesyl diphosphate to pentalenene. Orthogonal stereochemistry in an enzyme-catalyzed S(E') reaction
Pentalenene synthase catalyzes the cyclization of farnesyl diphosphate to (1) the sesquiterpene hydrocarbon pentalenene (4). Separate incubations of (4S,8S)-[4,8-3H2, 4,8-14C2]farnesyl diphosphate and (4R,8R)-[4,8-3H2, 4,814C2]farnesyl diphosphate with pentalenene synthase isolated from Streptomyces UC5319 and analysis of the derived labeled pentalenenes, 4a and 4b, respectively, by chemical degradation established that H-8si of FPP was lost upon cyclization to pentalenene. Consideration of the plausible conformations of the enzymatic cyclization intermediates indicates that the electrophilic allylic addition elimination (S(E')) reaction in which the C-4,5 bond of pentalenene is formed involves an orthogonal relationship between the C-C bond being formed and the C-H bond that is ultimately broken.
Cane,Weiner
p. 118 - 127
(2007/10/02)

Reaction of Azoalkanes with Isolable Cation Radical Salts
Three tertiary azoalkanes related in the sense acyclic, cyclic, and bicyclic are shown to evolve nitrogen upon oxidation with stable cation radical salts.Thus azo-tert-octane (ATO), 3,3,6,6-tetramethyl-1,2-diazacyclohexene (TMDAC), and 1,4-dimethyl-2,3-diazabicyclooct-2-ene (Me2DBO) react rapidly with thianthrenium perchlorate (Th(.1+)ClO4(1-)), tris(p-bromophenyl)aminium hexachloroantimonate (TBPA(.1+)SbCl6(1-)), and TBPA(.1+)SbF6(1-).The ether and olefin products, which are formed in high yield in CH2Cl2/MeOH solvent, are not those expected from the usual free-radical decomposition of azoalkanes but instead implicate carbocations.Althrough the reaction stoichiometry clearly requires 2 equiv of cation radical salt to one of azoalkane, the mechanism is not yet clearly defined.A complication in these studies is found in the ability of certain cation radical salts to oxidize more azoalkane than expected based on the 2:1 stoichiometry.
Engel, Paul S.,Robertson, Donald M.,Scholz, John N.,Shine, Henry J.
p. 6178 - 6187
(2007/10/02)

Tailor-made silylating agents for efficient surface modification
N-Silyldimethylamines are efficient silylating agents for the chemical surface modification of hydroxylated silicon dioxide preparations. The synthesis of chloro(5-X-3,3-dimethylpentyl)-dimethyl-silanes and their conversion to the corresponding (dimethylamino) silanes are described, where X is a methoxy, methoxymethoxy, cyano or dimethylamino group. The bulky substituent forms a two stage protecting layer at the surface. The second stage hinders the access of nucleophiles to the silicon atom resulting an enhanced hydrolytic stability.
Schneider,Cloux,Foti,Kovats
p. 1027 - 1031
(2007/10/02)

(Dialkyl-1,1 propene-2-yl)-2 thiazolidines: synthese regioselective et hydrolyse en aldehydes β-ethyleniques α,α-disubstitues
We describe a convenient method leading to α,α-disubstituted β-ethylenic aldehydes by hydrolysis of 2-(1,1-dialkyl 2-propenyl) thiazolidines, which are easily prepared by reaction between gem-disubstituted allylic Grignard reagents and 4,5-dihydrothiazoles.
Laduranty, Joelle,Barbot, Francis,Miginiac, Leone
p. 850 - 855
(2007/10/02)

(+)-α-Bisabolol and (+)-Anymol. A Repetition of the Synthesis from the Limonene 8,9-Epoxides
A repetition of Kergomard and Veschambre's determination of configuration for (+)-α-bisabolol has provided further evidence for the R,R-configuration, contrary to the original report. (+)-Anymol has the 4R,8S-configuration.
Carman, Raymond M.,Duffield, Alan R.
p. 2035 - 2039
(2007/10/02)

Reactions of 9-Substituted Fluorenide Carbanions with Allyl Chlorides by SN2 and SN2' Mechanism
The average ratio of SN2 rate constants for benzyl chloride vs. allyl chloride reacting with 9-substituted fluorenide carbanions, 9-G-Fl- (G = Me, PhS, Ph o-tol, or t-Bu), in Me2SO solution is 2.3, which is close to the ratio previously observed for reactions of smaller nucleophiles with more localized charges, such as iodide ion, in various solvents.Broensted plots of log k vs. pKHA (both in Me2SO) are used to calculate reactivity values (r) for 9-G-Fl- ions of the same basicity reacting with allyl chloride.The r values reveal the same order of steric effects for G in these SN2 reactions as was found previously for benzyl chloride, i.e., Me - ions were found to increase progressively and appreciably with γ-methyl substitution, i.e., CH2=CHCH2Cl (1) , MeCH=CHCH2Cl (4) , Me2C=CHCH2Cl (5), whereas the Broensted β values decreased progressively.The second-order rate constants for reactions with families of 9-G-Fl- ions were found to follow a somewhat different pattern for α-methyl substitution, i.e., CH2=CHCH2Cl (1) > CH2=CHCH(Me)Cl (2) CH2=CHC(Me)2Cl (3); the rate differences were small, but the β values again decreased progressively.Product studies indicated that 1 reacts with 9-G-Fl- ions by an SN2 mechanism but that 2 gives SN2' products in a amounts increasing along the series G = Me, Ph, o-tol, t-Bu; 3 appears to give only SN2' products.The rates of reactions of 9-CN-Fl- and 9-CO2MeFl- ions with 3 to form SN2' and SN2 products are independent of the carbanion concentration.The first-order reaction of 9-CN-Fl- ion with t-BuCl in MeOH gives 17percent yield of 9-CN-9-t-BuFl.Entalpies of activation for SN2 reactions of 9-G-Fl- ions reacting with 5 are 7-9 kcal/mol lower, and entropies of activation are 18, or more, eu units less positive than for SN2' reactions of 9-G-Fl- ions with 3.Mechanism for SN2' reactions are discussed in light of these findings.
Bordwell, Frederick G.,Clemens, Anthony H.,Cheng, Jin-Pei
p. 1773 - 1782
(2007/10/02)

HIGHLY ENANTIOSELECTIVE ISOMERIZATION OF PROCHIRAL ALLYLAMINES CATALYZED BY CHIRAL DIPHOSPHINE RHODIUM(I) COMPLEXES. PREPARATION OF OPTICALLY ACTIVE ENAMINES
Rh(I) complexes of types ClO4 and n>ClO4 (diphosphine = cis-chelating tertiary diphosphine; diene = 1,5-cyclooctadiene or norbornadiene; S = solvent) were found to be effective catalists for allylic hydrogen migration of tertiary and secondary allylamines to give the corresponding (E)-enamines and imines, respectively.Studies on diphosphine ligands with respect to the catalytic activity and product selectivity led to the discovery of a fully aryl-substituted diphosphine, BINAP , which produces very active Rh(I) complex catalysts.With ClO4 (COD = 1,5-cyclooctadiene) or n>ClO4 as catalyst, (Z)-(diethylnerylamine, 1) or (E)-N,N-diethyl-3,7-dimethyl-2,6-octadienylamine (diethylgeranylamine, 2) was isomerized into the racemic (E)-enamine (E)-N,N-diethyl-3,7dimethyl-1,6-octadienylamine (citronellenamine, 3) with a chemical selectivity of over 95percent, the 6-double bond being retained intact.A variety of substituted allylamines serves as the substrate, e.g., (E)-N,N-dimethyl-2-butenylamine, N,N-dimethyl-2-methyl-2-propenylamine, N,N-dimethyl-3-methyl-2-butenylamine, N,N-dimethyl-3-phenyl-2-butenylamine.Asymmetric isomerization of prochiral allylamines producing optically active enamines or imines can be effected with cationic Rh(I) complexes of various chiral diphosphine ligands such as (2R,3R)-DIOP and others.The ligand that gives the highest optical yield was (+)- or (-)-BINAP.Virtually perfect enantioselectivity (95-99percent ee) was achieved with + for the isomerization of 1 or 2 into the optically active (E)-enamine (3).A clear stereochemical correlation was established between the olefin geometry (E or Z) of substrates, the configuration of the chiral diphosphines (R or S), and the chiral carbon configuration of the product enamines (R or S).The present catalytic system thus provides a convenient and practical access to optically active aldehydes.For example, optically pure natural citronellal can be produced either from nerylamine with the Rh(I)-(+)-BINAP catalyst or from geranylamine with the Rh(I)-(-)-BINAP complex catalyst.
Tani, Kazuhide,Yamagata, Tsuneaki,Akutagawa, Susumu,Kumobayashi, Hidenori,Taketomi, Takanao,et al.
p. 5208 - 5217
(2007/10/02)

Synthesis of 1,2,3,3,6,6-Hexamethyl-1-cyclohexene - A Cascade of C12H23+ Carbenium Ion Rearrangements
6-Chloro-2,6,7,7-tetramethyl-2-octene (4), prepared via prenyl chloride addition to 2,3,3-trimethyl-1-butene, at room temperature undergoes a zinc chloride/hydrogen chloride-catalysed cyclocondensation to yield 1,2,3,3,6,6-hexamethyl-1-cyclohexene (1).The reaction mechanism is elucidated by isolation of intermediate five-membered carbocycles and by force field calculations.
Mayr, Herbert,Klein, Herbert,Sippel, Elfriede
p. 3624 - 3630
(2007/10/02)

Copper(I)-Mediated Synthesis of cis-Isoprenoids. Models for Natural Rubber
Two copper(I)-mediated routes for the preparation of all-cis-2,6,10-trimethyl-2,6,10-dodecatriene are investigated.Reaction of the Grignard reagent derived from 1-bromo-4-methylpent-3-ene with CuBr, and then with excess propyne, gave a vinylcopper intermediate which could be alkylated with 1-iodo-3-methylpent-3-ene, to afford the required triene stereospecifically cis- in 28percent yield.Iodination of the same intermediate and subsequent conversion to 1-bromo-4,8-dimethyl-3,7-nonadiene is shown to occur with retention of configuration, so allowing the iterative construction of cis-isoprenoids.This vinylcopper-based route is shown to be also applicable to the synthesis of larger cis-isoprenoids.In contrast, the CuI-modified coupling reaction of the Grignard reagent from 1-chloro-2-methylbut-2-ene with neryl chloride gave a mixture of triene isomers.
Parr, William J. E.
p. 4101 - 4130
(2007/10/02)

Improvements in the Hexachloroacetone/Triphenylphosphine Procedure for the Conversion of Allylic Alcohols into Chlorides
-
Magid, Ronald M.,Talley, Brenda G.,Souther, Stephen K.
p. 824 - 825
(2007/10/02)

Halogen Epoxides, 4. Synthesis, Stability and Reactions of 2-Chloro-2-(1-chloroalkyl)oxiranes with AgBF4
Reactions of 3-chloroperbenzoic acid with 2,3-dichloro-1-butene (1a), 2,3-dichloro-3-methyl-1-butene (1b), (Z)- and (E)-1,2-dichloro-2-butene (1c, d) and with 1,2-dichloro-3-methyl-2-butene (1e) afforded the corresponding epoxides (2a - e).They rearranged slowly at room temperature and fast at elevated temperatures to form the corresponding isomeric α,α'-dichloroketones (3a, b).Reactions of the epoxides with AgBF4 produced α-chloro-α'-fluoroketones.
Griesbaum, Karl,Lie, Giu Oan,Raupp, Erwin
p. 3273 - 3280
(2007/10/02)

Electrochemical Conjugate Additions of the Allyl Groups in Substituted Allyl Halides to α,β-Unsaturated Esters
Electrolysis of allyl halides and diethyl fumarate (2) in N,N-dimethylformamide containing 0.2 M tetraethylammonium tosylate gave a conjugate addition product, ethyl 3-(ethoxycarbonyl)-5-hexenoate, in a moderate yield.The electrochemical reaction of 1-chloro-3-methyl-2-butene (4) with 2, that of allyl chloride 4 with methyl crotonate (6), and that of methyl 4-halo-2-butenoate with 2 likewise gave the corresponding conjugate addition products, ethyl 3-(ethoxycarbonyl)-6-methyl-5-heptenoate, methyl 3,4,4-trimethyl-5-hexenoate, and ethyl 3-(ethoxycarbonyl)-4-(methoxycarbonyl)-5-hexenoate, respectively.The addition reaction of 4 to 2 takes place at the α-carbon terminus of 4 exclusively, whereas the addition of 4 to 6 at the γ-carbon terminus of 4 .These regioselectivities of the additions and pathways of the reactions are discussed.
Satoh, Shohei,Suginome, Hiroshi,Tokuda, Masao
p. 3456 - 3459
(2007/10/02)

(E-Z)-ISOMERISATION OF CHLOROOLEFINS
Equilibrium constants for the (E-Z)-isomerisation of the compounds R-CH=CH-Cl were determined and the experimental values compared with energy differences, calculated by the CNDO/2 method.
Prochazka, Milos,Adamcova, Jindriska,Palecek, Milos
p. 1388 - 1400
(2007/10/02)

REACTIONS OF CARBONYL COMPOUNDS IN THE PRESENCE OF PHASE-TRANSITION CATALYSTS. 4. STUDY OF THE REACTION OF ACETOACETIC ESTER WITH 1-CHLORO-3-METHYL-2-BUTENE IN THE PRESENCE VARIOUS ALKALINE AGENTS
-
Esikova, I. A.,Yufit, S. S.
p. 328 - 335
(2007/10/02)

Process for the preparation of unsaturated ketones
Ketones, which are intermediates in the synthesis of vitamin A or perfumes, and have the general formula: EQU1 wherein R1 is hydrogen or C1-10 hydrocarbon, R2 and R3 are hydrogen or C1-4 alkyl, R4 and R5 are hydrogen or together form a --CH2 --CH2 --C(CH3)2 -- group, R6 and R7 are hydrogen or C1-10 hydrocarbon, or together with the carbon atom to which they are joined form a hydrocarbon ring of up to 10 carbons, or EQU2 forms a hydrocarbon ring of up to 10 carbons joined through R6 and R8 or R7 and R8, R8 is hydrogen or C1-10 hydrocarbon and n is 0-6, are prepared by reacting an unsaturated halide of formula EQU3 wherein X is halogen, with an enol ester of formula EQU4 wherein R9 is C1-20 hydrocarbon, in the presence of a metal catalyst.
-
(2008/06/13)

Novel indolobenzazepine derivatives, useful as tranquilizers
Certain novel 1,2,3,4,8,9-hexahydro-3-(substituted)pyrido[4',3':2,3]indolo[1,7-ab][1]-benzazepines are useful as minor tranquilizers (anxiolytics) and/or major tranquilizers (antipsychotics). The minor tranquilizers are effective at non-ataxic doses, and are not likely to cause addiction when abused. A representative compound in this class is 3-(cyclopropylmethyl)-1,2,3,4,8,9-hexahydropyrido[4',3':2,3]indolo[1,7-ab][1]benzazepine.
-
(2008/06/13)