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A sulfonyl promoted synthetic protocol for the C-3 alkylation of trans-3-phenylsulfonyl-β-lactams 6(a-e) with active organic halides in presence of K2CO3 as mild base and DMF as solvent is described. This protocol furnished cis- and trans-β-lactams as major and minor isomers respectively with alkyl halides while arylalkyl/unsaturated halides yield only cis-β-lactams exclusively. Further, the effect of sterically bulky group on the C-3 substitution was investigated by the reaction of 3-phenylsulfonyl-β-lactams 6(d-e) with crotyl chloride (predominantly E) to achieve diastereomeric mixture of β-lactams 7/7ʹ and 8. This strategy reveals advantages in terms of cost effectiveness, functional group tolerance and ease of operation.

This paper describes the codimerization of n -butenes with allylic halides such as cinnamyl chloride and crotyl chloride. The highly active catalyst RhCl 3 ·3H 2 O was investigated, resulting 70% yield of codimers with cinnamyl chloride and 1-butene. Furthermore, the reaction is dependent on the molar ratio of allylic chloride to RhCl 3 ·3H 2 O ratio, where a ratio of 75:1 is optimal at a catalyst concentration of 2 mol%. Additionally allylic compounds such as cinnamyl chloride lead to higher yields of the codimer than other short chained allylic chlorides. So the codimerization of an allylic compound with 1-butene represents a simple method to produce short chained dienes at very mild reaction conditions.

The development of the first enantio-, diastereo-, and regioselective iridium-catalyzed allylic alkylation reaction of prochiral enolates to form an all-carbon quaternary stereogenic center with an aliphatic-substituted allylic electrophile is disclosed. The reaction proceeds with good to excellent selectivity with a range of substituted tetralone-derived nucleophiles furnishing products bearing a newly formed vicinal tertiary and all-carbon quaternary stereodyad. The utility of this protocol is further demonstrated via a number of synthetically diverse product transformations.

The complex [PtMe2(2,2′-bipyridine)], 1, reacts with allyl chloride and allyl bromide, to give [PtXMe2(CH2CH═CH2)(2,2′-bipyridine)], 2, X = Cl; 3, X = Br, with 2-methylallyl chloride to give [PtClMe2(CH2CMe═CH2)(2,2′-bipyridine)], 4, and with crotyl chloride (a mixture of trans- and cis-MeCH═CHCH2Cl), to give a mixture of [PtClMe2(trans-CH2CH═CHMe)(2,2′-bipyridine)], 5, and [PtClMe2(cis-CH2CH═CHMe)(2,2′-bipyridine)], 6. The complexes are formed mostly by trans oxidative addition and, for the crotyl complexes, without allylic rearrangement. Complex 1 reacts with CH2═CHCHMeCl, mostly with allylic rearrangement, to give complex 5, with complexes 6 and [PtClMe2(CHMeCH═CH2)(2,2′-bipyridine)], 7, as minor products. The reactions of 1 with CH2═CHCH2X (X = Cl or Br) and MeCH═CHCH2Cl follow second-order kinetics (first-order in both reagents), but 1 reacts with CH2═CHCHMeCl by third-order kinetics (first-order in 1, second-order in CH2═CHCHMeCl) and with CH2═CMeCH2Cl by a mixture of second- and third-order kinetic...

A novel mediator (Sn/I2) has been developed and employed in the allylation and crotylation of various aldehydes and ketones with allyl (crotyl) halide in water. With a catalytic amount of I2 and less than stoichiometric amounts of Sn, allyl (crotyl) bromide reacts with carbonyl compounds to produce the corresponding alcohols in quantitative yield. Even the inert allyl chloride and crotyl chloride can react with aldehydes to give the corresponding alcohols. The diastereoselectivity and regioseletivity of the reaction have also been studied. Sn/I2 mediated allylations of aldehydes with crotyl bromide produced dominant γ-adducts with minor α-isomers while Sn/I2 mediated allylations of aldehydes with crotyl chloride afforded dominant α-adducts with minor γ-isomers.

Sodium sucrates have been investigated as a means of preparing sucrose derivatives from organic halogen compounds. No reaction has been effected with monosodium sucrate and methyl iodide, and this has been attributed to the presence of ammonia or sodamide in the sucrate. A product approximating in composition to a tetra-O-allyl sucrose has been obtained in 50% yield from trisodium sucrate and allyl chloride at 122°; allyl sucrose has also been prepared from hexasodium sucrate. Mono., tri-, penta- and hepta-sodium sucrate react with epichlorohydrin at 135° to give in quantitative yield highly cross-linked insoluble polymers of the epoxide resin type; mixtures of sucrose and sodium sucrate also give insoluble polymers. Methoxymethyl sucrose, soluble in water and organic solvents, has been prepared from chloromethyl methyl ether and pentasodium sucrate at 15°. Ethylene dichloride reacts with trisodium sucrate at 122–135° but sucrose is the major product formed. o-Chloronitrobenzene does not react. The reactivity of pentasodium sucrate towards a range of organic compounds has been assessed under mild conditions in the presence of dimethoxyethane: (a) alkyl and aryl chlorides in general do not react at 70–75°, but crotyl chloride is an exception and crotyl sucrose has been prepared in 62% yield; (b) acid chlorides and simple acid anhydrides react readily and 15 crude sucrose esters have been prepared and their solubilities estimated. Terephthaloyl sucrose is a polymer. Complex reactions occur with triphenylmethyl chloride, picryl chloride, 2: 4-dichlorophenoxyacetyl chloride, a-chloroacetophenone and ethyl mercuric chloride.

The kinetics and mechanisms of chlorine atom reactions with the products of organic oxidations in the atmosphere are of interest for understanding the chemistry of coastal areas. We report here the first kinetics measurements of the reactions of atomic chlorine with 4-chlorocrotonaldehyde and chloromethyl vinyl ketone, recently identified as products of the reaction of chlorine atoms with 1,3-butadiene. The reactions with acrolein, methacrolein, crotonaldehyde, methyl vinyl ketone and crotyl chloride were also studied to probe structure-reactivity relationships. Relative rate studies were carried out at 1 atm and 298 K using two different approaches: long path FTIR for the acrolein, methacrolein, crotonaldehyde and methyl vinyl ketone reactions with acetylene as the reference compound, and a collapsible Teflon reaction chamber with GC-FID detection of the organics using n-butane or n-nonane as the reference compounds for the entire series. The average absolute rate constants (in units of 10−10 cm3 molecule−1 s−1) determined using these techniques are as follows: acrolein (2.5 ± 0.7); methacrolein (2.9 ± 0.8); crotonaldehyde (3.2 ± 0.9); methyl vinyl ketone (2.0 ± 0.5); 4-chlorocrotonaldehyde (1.6 ± 0.4); chloromethyl vinyl ketone (2.0 ± 0.2); crotyl chloride (2.5 ± 0.2). The reported errors are ±2σ and include a reference rate constant error of 20% for acetylene, 10% for n-butane and 3% for n-nonane. These values are in good agreement with previous literature reports for the acrolein, methacrolein and methyl vinyl ketone reactions, while that for crotonaldehyde is 33% larger. The rate constant for acetylene using n-butane as the reference compound was also measured to be (5.23 ± 0.91) × 10−11 cm3 molecule−1 s−1 (2σ), in excellent agreement with the currently recommended value at 1 atm and 298 K. The effect of structure on reactivity of these compounds is discussed and it is shown that these fast reactions will be a major loss process for these compounds in coastal marine areas at dawn.

Two series of new bidentate P–N ligands have been synthesized. Application of these ligands in the palladium catalysed allylic alkylation of crotyl chloride and cinnamyl chloride leads to the preferential formation of the branched product. A larger bite angle of the ligand leads to higher regioselectivity. Stoichiometric alkylation of the complex [Pd(C4H7){p-MeOC6H4CN(CH2)4OPPh2}][O3SCF3] proceeds with 88% regioselectivity to the branched product.

The deaminations of trans-2-methyl- and 2-phenylcyclopropylamine hydrochlorides in acetic acid solution have been examined. A major product in each case was an allylic chloride, and the amount of chlorides increased when the chloride ion concentration was increased. With the methyl-substituted amine, increasing the chloride ion concentration changed the major chloride product from crotyl chloride to methallyl chloride. The addition of lithium perchlorate led to a reduction in the amount of chlorides formed. These results indicate that an ion pair is involved in the reaction. The deamination of the related open chain amines gave only small amounts of chlorides. B3LYP/6-31G* calculations found cyclopropyldiazonium chloride to prefer to have the chloride ion over the cyclopropyl ring. The transition state was located, and when followed down to products, allyl chloride was found. Similar calculations for the methyl-substituted series led to crotyl chloride from the ion pair with one chloride ion and to methal...

The Raman spectra of cis, trans, and vinyl isomers of crotyl chloride (i.e., cis and trans 1-chloro-2-butene, and 3-chloro-1-butene) have been excited at 218 nm and at 231 nm. With 218-nm excitation the ethylenic mode belonging to the vinyl isomer is only modestly preresonance enhanced. On the other hand, the preresonance enhancement of the peaks belonging to the cis and trans isomers is very noticeable and nearly identical in energy to the peaks of cis and trans polybutadiene, which occur at 1655 and 1665 cm−1, respectively. However, with 231-nm excitation the vinyl-isomer ethylenic mode at 1633 cm−1 is very strongly enhanced, while the cis and trans isomer modes show no corresponding enhancement, but appear to decrease in relative intensity. Responsibility for the strong vinyl group enhancement is assigned to an electronic transition observed as a broad shoulder near 230 nm. By exciting at 231 nm it is possible to detect small amounts of the vinyl isomer in the presence of cis and trans crotyl chloride. Remarkably strong enhancement under 231-nm excitation has been noted as well for the first overtone of the vinyl ethylenic mode observed at 3263 cm−1.

The various modifications of the Cope and Claisen rearrangements have been developed in recent years and these methods have proved very useful for the natural product synthesis owing to their high stereoselectivities. 1 Nozaki et al. 2 Although found the stereoselective trisubstituted olefin synthesis via a thio-Claisen rearrangement in 1973, only a few reports have appeared on this rearrangement so far. 3 Takano et al. reported an a-allylation of thioamides via a thio-Claisen rearrangement 4a and its successful application to the indole alkaloid synthesis. 4b In this communication we wish to report the first example of the double thio-Claisen and Cope rearrangements, which furnish cl,Bc

The reactions of allyl bromide and crotyl chloride with Grignard reagent catalyzed by π-allyl and crotyl metal complexes of nickel, cobalt, and iron, and the stoichiometric reaction of the complexes with the Grignard reagent have been examined. The similarity in catalytic behaviour of the complex and the corresponding metallic halide affords further evidence in support of the previous proposal that the π-allylic metal intermediate plays an important role in the catalytic reaction. The stoichiometric reaction suggests that the dependence of distribution of product in the catalytic process on the type of both allylic halide and metal is attributable to the facility of ligand exchange between the π-allylic complex and Grignard reagent.

A detailed study has been made of the oxidative addition reaction of allylic halides to IrCI(CO)(P(CH 3 ) 2 C 6 (H 5 ) 2 in benzene in methanol. In benzene the reaction probably occurs by way of a π-allyl intermediate. This reacts with anion to give a product with α o-ally group bonded to the metal cis to the added anion. Both crotyl α-methylallyl chlorides give the same products since they form the same π-allyl. In methanol the π-allyl is not an intermediate since crotyl chloride α-methylallyl chloride give different σ-allyl products with the metal atom bonding predominantly to the carbon atom bearing the chloride. The anion which add in methanol can be one added to the solution it bonds trans to the σ-allyl group. A modified S N 2 mechanism with double-bond participation is proposed for both solvents.

The relative alkylating capabilities of crotyl chloride, allyl bromide, and 1-bromo-2-butyne with respect to compounds containing thiol, imidazole, primary amino, and methylthio functions representative of those present in cysteine, histidine, lysine and methionine residues have been studied using 2-bromoacetophenone as the reference alkylating agent.

The telomerizations of butadiene with its hydrochlorides (1-chlorobutene-2 and 3-chlorobutene-1) in several sorts of solvents in the presence of Lewis acids were investigated. Titanium tetrachloride in ethyl bromide has a considerable catalytic ability at low temperatures and gives telomers with higher average molecular weights than ferric chloride and aluminum chloride at almost the same conversions of reaction. On the other hand, antimony pentachloride gives only a small amount of product with lower average molecular weights. The telomerizations in methylene dichloride and chloroform give almost the same amounts of telomers with molecular weights higher somewhat in the former solvent than the latter. The telomerization in toluene gives primarily the products of Friedel-Crafts reaction, and a small amount of telomers of butadiene with crotyl chloride is obtained. The use of ethyl ether, acetonitrile and acetic anhydride as solvents at low temperatures in the presence of ferric chloride affords poor yield...

A series of representative allylic chlorides was hydroborated with borane-tetrahydrofuran and disiamylborane. Hydroboration of allylic chlorides containing a symmetric double bond placed the boron exclusively at the β-position. Dissymmetric double bonds having more β-substitution than γ-substitution react to place the boron predominantly on the γ-carbon with borane-tetrahydrofuran and almost exclusively on the γ-carbon with disiamylborane. In the hydroboration of crotyl chloride with diborane, the rate of elimination of the β-chloroorganoborane slows markedly after 80% elimination. The 20% of slow elimination reflects the amount of dihydroboration which occurs before elimination. The dialkylborane thus formed probably dimerizes and the dimer undergoes elimination at a reduced rate. The slow elimination is subject to Lewis acid catalysis.

Trichlorosilane undergoes a smooth reaction at room temperature with allyl chloride, β-methallyl chloride, crotyl chloride, and α-methallyl chloride to give the corresponding allyltrichlorosilanes in excellent yields in the presence of an equimolar amount of a tertiary amine and a catalytic amount of a metal salt such as cuprous chloride.

A four-step synthesis of (RS)-carnitine chloride was developed using extremely mild reaction conditions and versatile intermediates. Crotyl chloride was converted to tert-butyl 3-butenoate using tert-butyl alcohol and triethylamine in ether. Treatment of tert-butyl 3-butenoate with m-chloroperbenzoic acid in chloroform afforded tert-butyl 3,4-epoxybutyrate. Reaction of this compound with trimethylamine hydrochloride in methanol, followed by mild acid hydrolysis of the tert-butyl ester, afforded (RS)-carnitine chloride.

A four-step synthesis of (RS)-carnitine chloride was developed using extremely mild reaction conditions and versatile intermediates. Crotyl chloride was converted to tert-butyl 3-butenoate using tert-butyl alcohol and triethylamine in ether. Treatment of tert-butyl 3-butenoate with m-chloroperbenzoic acid in chloroform afforded tert-butyl 3,4-epoxybutyrate. Reaction of this compound with trimethylamine hydrochloride in methanol, followed by mild acid hydrolysis of the tert-butyl ester, afforded (RS)-carnitine chloride.