Cyclohexene 1-iodo

B. (Z)-l-Iodo-l-heptene.2 A solution of 8.52 g of (112 mmol) of borane-dimethylsulfide complex (Note 13) in 100 mL of ether is added to a flame-dried, three-necked, 300-mL, round-bottomed flask equipped with stirbar, temperature probe, and N2 inlet. The solution is cooled to 5°C with an ice-bath. Cyclohexene (18.4 g, 224 mmol) (Note 14) is then added by syringe over 10 min while keeping the temperature below 15°C. The mixture is stirred at 5°C for 15 min. A white solid precipitates either towards the end of the addition or during the subsequent stirring period. The reaction mixture is allowed to warm to room temperature and is stirred for 1 hr. The non-homogeneous solution is cooled to 2-3°C... 

Ethylenedioxybutyl)-3-trichloro-acetamido-l-cyclohexene, 58, 9, 11 Ethylene glycol, 56, 44 Ethyl a-fluoro-l-naphthaleneacetate, 57, 73 Ethyl 2-fluoropropanoate, 57, 73 3-Ethylhexane, 58, 3, 4 3-ETHYL-l-HEXYNE, 58, 1, 2, 3, 4 Ethylidenecyclohexane, 59, 46 Ethyliodide, 59, 133 Ethyl 2-iodo-3-nitropropionate, 56,65 Ethyl isocyanide, 55, 98 Ethyl isocyanoacetate, 59,184 l-Ethyl-4-isopropylbenzene, 55,10 Ethyl levulinates, 5-substituted, 58, 81 ETHYL 2-METHYL1NDOLE-5CARBOXY-LATE, 56, 72... 

The 5,6-disubstituted dihydropyran 2049 is converted by iodosobenzene diacetate and Me3SiBr 16 or Mc3Sil 17 in pyridine to the 3-bromo (or 3-iodo) compounds 2050 in 79 or 84% yield, respectively [198] (Scheme 12.59). Reaction of olefins such as cyclohexene (or enol ethers) with iodosobenzene diacetate, tetra-... 

A unique system for catalytic silaboration of allenes, in which a catalytic amount of organic halide is used as a crucial additive, has been reported (Equation (86)).232 In the presence of Pd2(dba)3 (5 mol%) with 3-iodo-2-methyl-2-cyclohexen-l-one (10mol%), reactions of terminal allenes with a silylborane afford /3-silylallylboranes in good yields with excellent regioselectivity. It is worth noting that the addition takes place at the terminal C=C bond in contrast to the above-mentioned palladium-catalyzed silaboration. The alkenyl iodide can be replaced with iodine or trimethylsilyl iodide. The key reaction intermediate seems to be silylpalladium(n) iodide, which promotes the insertion of allenes with Si-C bond formation at the central -carbon. 

This material is recrystallized from diethyl ether/pentane (2 1) to give 15.1 g (69%) of 2-iodo-2-cyclohexen-1-one as a pale yellow solid, mp 48.5-49°C (Note 7). If desired, an additional 2.4 g (11% mp 48-49°C) can be isolated by concentration of the mother liquor, column chromatography of the residue on 40 g of silica gel eluting with a mixture of 10% ethyl acetate in petroleum ether, and recrystallization of the collected iodoenone from pentane. 

B. 2-(4-Methoxyphenyl)-2-cyclohexen-1-one. A 500-mL, round-bottomed flask, equipped with a 1.5-in. Teflon-coated magnetic stirring bar and an argon inlet adaptor, is charged with 10.02 g (45.1 mmol) of 2-iodo-2-cyclohexen-1-one, 10.69 g (70.4 mmol, 1.56 eq) of 4-methoxyphenylboronic acid (Note 8), 16.72 g (72.1 mmol, 1.6 eq) of silver(l) oxide (Ag20) (Note 9), 0.85 g (2.8 mmol, 6 mol %) of triphenylarsine (Note 10), 0.53 g (1.4 mmol, 3 mol %) of palladium(ll) bis(benzonitrile)dichloride (Note 11), 200 mL of tetrahydrofuran (THF) and 25 mL of water (Note 12). The reaction mixture, flushed with argon, is stirred for 1 hr and then quenched by the addition of 125 mL of saturated aqueous ammonium chloride. After the solution is stirred for 1 hr, the... 

The Suzuki coupling of 2-iodo-2-cyclohexen-1-one and 4-methoxy-phenylboronic acid is achieved using silver(l) oxide as a suspension in aqueous THF as the base. Unlike earlier reports,15-17 in which up to 6 equiv of Ag2mild conditions, rapid conversion can be achieved at room temperature for a large variety of sensitively functionalized partners in near quantitative yields (see Table).18... 

METHOXYPHENYL)-2-CYCLOHEXEN-1-ONE PREPARATION OF 2-IODO-2-CYCLOHEXEN-1-ONE AND SUZUKI COUPLING WITH 4-METHOXYPHENYLBORONIC ACID (2-Cyclohexen-1-one, 2-(4-methoxyphenyl)- and 2-Cyclohexen-1-one, 2-iodo-)... 

PREPARATION OF 2-IODO-2-CYCLOHEXEN-1 -ONE AND SUZUKI COUPLING WITH 4-METHOXYPHENYL BORONIC ACID... 

Similarly, the oxidation of iodocyclohexane by DMD under a nitrogen-gas atmosphere leads to the iodohydrin and diol as unexpected products (equation 24). The iodohydrin, formed as the major product, clearly reveals that hypoiodous acid (HOI) is generated in situ, which adds to the liberated cyclohexene. Indeed, when methyl iodide (Mel) is oxidized by DMD at subambient temperature in the presence of cyclohexene, the corresponding iodohydrin is obtained in very good yield The latter method may be utilized for the preparation of allylic alcohols with a vinylic iodo functional group from allenes (equation 25) . ... 

Thua cyclohexene sulfide reacts slowly at room temperature in the presence of a slight excess of methyl iodide to form (LXVITI) in about 60% yield.1 With the simpler episulfides, e.ff. ethylene sulfide and propylene Bulfide, a complex mixture of salts is obtained unless a large excess of methyl iodide is employed to suppress the competitive qu ternization of the episnlfide by intermediate iodo compounds such as (IiXlX), Apparently no simple methyl 2-iodoethyl sulfide (LXIX) has been isolated from this type of reaction, nor have other expected fragments such as the olefin (LXX) or the diiodide (LXXI). 

Treatment of owK-l-iodo-2-(pcrfluoropropyl (cyclohexane (trans-H 1) with sodium methoxide gives 3-(perfluoropropyl)cyclohexene (33) in a yield of 64% via anti elimination and l-(per-fluoropropyl)cyclohexene (32) in a yield of 13% via syn elimination of hydrogen iodide.77... 

Cyclohexene oxide was first prepared by Brunei from o-iodo-cyclohexanol and solid potassium hydroxide.1 It has also been obtained by the oxidation of cyclohexene with benzoyl hydroperoxide.2... 

Nitrosonium ion was found to promote iodination of cyclohexene when AcOH was used as solvent, the trans-iodo acetoxy derivative was formed in a good yield. Solvolysis of the latter, followed by saponification, led to a cA-diol so that this method can serve as an alternative to the wet-Prdvost reaction. The NO+ cation is believed to promote the formation of some positive iodine species (equation 1). Oxidation by oxygen leads to the regeneration of iodine and NO+ from nitrosyl chloride189. 

Admixture of BAIB with two equivalents of trimethylsilyl isothiocyanate in dichloromethane leads to the rapid formation of thiocyanogen and iodoben-zene, presumably via [bis(thiocyanato)iodo]benzene (Scheme 10) [32]. The addition of alkenes to such solutions affords vzcmaZ-dithiocyanatoalkanes. Cyclohexene and its 1-methyl analog were converted exclusively to the transadducts under these conditions, while dihydropyran gave a 1 1 mixture of cis-and trans-isomers. 

More recently, the effect of substituents in the arenesulfonyl moiety on Cu(I)-catalyzed aziridinations of cyclohexene with a series of [(arenesulfonyl-imino)iodo]benzenes was evaluated (Scheme 65) [177]. Iminoiodanes possessing p-OMe,p-CF3, andp-N02 substituents gave higher yields of aziridines than the tosylimino analog. Product yields in these reactions are not simply related to relative rates of aziridination (p-MeO >p-Me >p-N02), and appear to reflect partitioning of the copper(III)-nitrene intermediates between aziridination of the C,C-double bond and reduction to the corresponding sulfonamides. 

The aliphatic iodane C3F7I(02CCF3)2 was reactive towards alkenes for example, with 1-hexene it gave 1,2-bis-trifluoroacetoxy-hexane (68%) with cyclohexene the quantitative formation of trans-1 -iodo-2-trifluoroacetoxy adduct occurred, at 0°C [59]. 

Some ylides from cyclic precursors are thermally labile and isomerize to iodo-enol ethers for example, the ylide of dimedone afforded 2-iodo-3-phenoxy-5,5-dimethyl-2-cyclohexanone [41], A similar reaction involving cleavage of the I-Cphenyi bond occurred with triethylphosphite 2-iodo-3-ethoxy-5,5-dimethyl-2-cyclohexen-l-one was the main product (65%) [42],... 

Lithium (phenylthiocyclopropylcuprate) 185, prepared by the reaction of cuprous thiophenolate with cyclopropyllithium in THF at —78 °C, was added to p-iodo-enones. For example, treatment with 3-iodo-2-cyclohexen-l-one 186 provided the corresponding P-cyclopropyl a,P-unsaturated ketones 187 with high efficiency, Eq. (59) 127). 

Acetoxyiodination of cyclohexene derivatives is acquired by the oxidative combination NCS/Nal/AcOH427. NBS/AcOH is the common reagent for acetoxybromination428. N-Bromoacetamide in acetic acid or water reacts with 1 l,12-dihydrobenzo[e]pyrene to yield the corresponding bromoacetate and bromohydrine, respectively429. KBr can also be used under oxidative conditions, e.g. coupled with peracid and 18-crown-6430. Iodo enol acetates are obtained by reaction of bis(pyridine)iodo tetrafluoroborate with acetylenes in acetic acid (equation 51)431. 

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