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Organoiodine compounds

In addition to its uses in photography and medicine, iodine and its compounds have been much exploited in volumetric analysis (iodometry and iodimetry, p. 864). Organoiodine compounds have also played a notable part in the development of synthetic organic chemistry, being the first compounds used in A. W. von Hofmann s alkylation of amines (1850), A. W. Williamson s synthesis of ethers (1851), A. Wurtz s coupling reactions (1855) and V. Grignard s reagents (1900). [Pg.794]

Leitner NKV (1998) Chlorination and formation of organoiodinated compounds the important role of ammonia. Environ Sci Technol 32 1680-1685. [Pg.44]

As indicated, only elemental iodine is found in the combustion products of organoiodine compounds [61,62,67]. The iodine formed in a static bomb is mostly in the crystalline state, but some is present in the aqueous and in the gaseous phases. The thermal corrections for dissolution and sublimation are very small and, therefore, static-bomb calorimeters may be used to study organoiodine compounds. However, to avoid the uncertainty in the final state due to the distribution... [Pg.113]

Organoiodine compounds are somewhat unusual in that their absorption cross sections are sufficiently red-shifted that they absorb in the actinic region (A > 290 nm) and hence photolyze in the troposphere. Use the data for Cl I, I in Table 4.42, Chapter 4, to estimate the lifetime of this compound with respect to photolysis at the earth s surface at a solar zenith angle of 50° on May 1. How does this compare to its lifetime with respect to reaction with OH at 1 X 106 radicals cm 3 if the rate constant is 7.2 X 10 14 cm3 molecule 1 s 1 ... [Pg.753]

M. Ochiai, Y. Nagao Hypervalent organoiodine compounds in organic synthesis reaction with organosilicon and tin [12]... [Pg.2]

D. Wang Application of hypervalent organoiodine compounds in synthesis [17]... [Pg.2]

Hypervalent organoiodine compounds have found wide utility in organic synthesis. Primary and secondary alcohols can be oxidized to aldehydes and ketones with the 12-1-5 compound (28), according to equation (29). a-Hydroxy dimethyl acetals can be synthesized under basic conditions with the 10-1-3 reagent PhI(OAc)2 (equation 30). The topic... [Pg.1668]

Ynol tosylates are synthesized from terminal alkynes via a unique sequence (equation 10). The hypervalent organoiodine compound 32, prepared by treatment of iodosoben-zene diacetate with /i-toluenesulfonic acid, reacts with the terminal alkynes 31 to give the iodonium tosylates 33, which are then treated with 10 mol% of CuOTf or AgOTf to afford the ynol tosylates 34. Finally, the ynol tosylates 34 are converted into lithium ynolates 35 by treatment with MeLi. The ynolates are trapped with r-butyldimethylsilyl chloride, triethylgermyl chloride and tributylstannyl chloride to give the silyl ynol ethers 36, the germyl ketenes 37 and the stannyl ketene 38. ... [Pg.745]

The generation of alkoxyl radicals from alcohols is an important process which has been used for remote functionalization via hydrogen atom abstraction and for rearrangement via -fragmentation. Hypervalent organoiodine compounds have been applied with success in this type of chemistry. More recently, tetravalent selenium compounds have been used for the same purpose [120]. An efficient way of making ether linkage from non-functionalized alcohols has been developed. The conversion of the alcohol 158 to the ether 159 is a key step in the synthesis of (-l-)-8-deoxyvernolepin [Eq. (51)] [121]. This transformation is best... [Pg.108]

The oxidative Hofmann rearrangement of primary carboxamides occurs by use of lead tetraacetate (LTA) and several hypervalent organoiodine compounds IF5 (28), PhI(OCOCP3)2 (29), PhI(OH)OTs (30) and PhIO (31) under mildly acidic conditions. [Pg.802]

Hydroxy(tosyloxy)iodobenzene (HTIB 30) is another hypervalent organoiodine compound which acts as a Hofmann reagent, converting aliphatic carboxamides to alkylammonium tosylates in refluxing acetonitrile (equation 23). [Pg.805]

Iodide was identified as the main iodine species in milk, but in a few samples also traces of iodate and several unidentified, presumably organoiodine, compounds were observed. [Pg.236]

Organoiodine compounds. lodoaienes, iodoaUcenes, and iodoalkynes are prepared from organolithiums by reaction with 2,2,2-trifluoroethyl iodide. [Pg.292]

Wacker-type oxidation. S fected with H2O2 in the presence 1 Epoxidation. (Salen)Mn con dation." Usually an imidazole is ai these oxidations. " A great variet in this process, including oxygen organoiodine compounds. [Pg.184]

Only a few organoiodine compounds are of environmental importance. Methyl iodide, a metabolic product of some marine and freshwater algae, produces CHj and I by direct photolysis (Zafiriou, 1983). [Pg.391]

Research activity in the area of polyvalent organoiodine compounds during the period between 1914 and 1970s was relatively low and represented mainly by valuable contributions from the laboratories of I. Masson, R. B. Sandin, F. M. Beringer, K. H. Pausacker, A. N. Nesmeyanov and O. Neilands. Only three significant reviews were published during this period, most notably the reviews by Sandin [17] and Banks [18] published in Chemical Reviews in 1943 and 1966, respectively and a comprehensive tabulation of the physical properties of polyvalent iodine compounds published in 1956 by Beringer [19]. [Pg.2]

The structural aspects of polyvalent iodine compounds were previously summarized in several books and reviews [20, 30, 32, 127]. In general, the molecular structure of and -iodanes is predetermined by the nature of hypervalent bonding discussed in Section 1.3. The key stmctural features of the hypervalent organoiodine compounds available from numerous X-ray data may be summarized as follows ... [Pg.8]


See other pages where Organoiodine compounds is mentioned: [Pg.108]    [Pg.707]    [Pg.708]    [Pg.3]    [Pg.356]    [Pg.346]    [Pg.214]    [Pg.53]    [Pg.55]    [Pg.621]    [Pg.621]    [Pg.240]    [Pg.256]    [Pg.22]    [Pg.107]    [Pg.107]    [Pg.544]    [Pg.545]    [Pg.7]    [Pg.12]    [Pg.102]    [Pg.143]    [Pg.146]    [Pg.2]    [Pg.2]    [Pg.3]    [Pg.9]   
See also in sourсe #XX -- [ Pg.402 ]




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