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Volume 43, Issue 2
Displaying 1-11 of 11 articles from this issue
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Akira SUZUKI, Shoji HARA1985 Volume 43 Issue 2 Pages 100-111
Published: February 01, 1985
Released on J-STAGE: January 22, 2010
JOURNAL FREE ACCESSAlthough the haloboration reaction would be considered to provide useful application to organic synthesis, the reaction has not adequately developed for such purposes.
Most recently, we found that B-halo-9-borabicyclo [3, 3, 1] nonane (B-X-9-BBN, X=Br or I) reacts with 1-alkynes stereo-, regio-, and chemoselectively. For example, the bromoboration of 1- alkynes with B-Br-9-BBN is very facile and complete within a few hours via a cis addition of the Br- B bond to the terminal triple bond. Such a reaction was confirmed to occur only at terminal triple bonds, but not at internal triple bonds, terminal and internal double bonds.
The sequential treatments of the haloboration products afford convenient methodologies of obtaining 2- halo- 1- alkenes, (Z) - 1- alkynyl -2- halo - 1- alkenes, (E) -and (Z) - 1, 2- dihalo- 1- alkenes, (Z) -δ- halo - γ, δ- unsaturated ketones, α- bromoaldehydes, 1, 1- dialkylethenes, 1- halo- 2, 2- dialkylethenes, trisubstituted ethenes and others.View full abstractDownload PDF (1068K) -
Ilhyong RYU, Noboru SONODA1985 Volume 43 Issue 2 Pages 112-120
Published: February 01, 1985
Released on J-STAGE: January 22, 2010
JOURNAL FREE ACCESSThe chemistry of β-metallo ketones (or β-metal substituted ketones) has been reviewed. Though attractive and promissing, their chemistry is almost undeveloped compared with rich chemistry of their α-counter part, i. e., α-metal substituted ketones or metal enolates. This may be due to lack in general method for generation of β-metal substituted ketones. The recent approach consisting of desilylative ring cleavage of siloxycyclopropanes with metal salts has been proven successful and has opened new entry to a variety of β-metal substituted ketones. Nonconventional methods for the bond formation at β to carbonyls have been developed with the aid of β-metal substituted ketones.View full abstractDownload PDF (1031K) -
Noboru ONO, Hideyoshi MIYAKE, Aritsune KAJI1985 Volume 43 Issue 2 Pages 121-132
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe nitro groups in tertiary or secondary nitro compounds are replaced by hydrogen or deuterium on treatment with tributyltin hydride or deuteride, respectively. This discovery opens a new area in organic synthesis, as a-anions of nitroalkanes can be used as equivalents of alkyl anions. Thus, following new synthetic reactions are devised on the basis of the denitrohydrogenation with Bu3SnH. (1) Conjugate addition of alkyl groups via Michael addition of nitroalkanes followed by denitration. (2) Synthesis of ketones via denitration of α-nitro ketones. (3) Synthesis of alcohols via denitration of β-nitro alcohols. (4) Regioselective deuteration. (5) New substitution reactions via radical substitution and denitration. (6) Regiocontrolled Diels-Alder reactions (7) Radical cyclization of aliphatic nitro compounds. (8) Synthesis of olefins.View full abstractDownload PDF (1092K) -
Development to Organic SynthesisMasaru KIMURA1985 Volume 43 Issue 2 Pages 133-144
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSIn recent years, many theoretical and experimental investigations concerning the role of exciplexes as intermediates in photocycloadditions have been accumulated. Electronically excited molecules are susceptible to molecular complex formation, and such complexes are commonly known as excimers and exciplexes. Electron transfer may occur following the complex formation which will lead to a number of interesting physical phenomena and chemical reactions. In this context author reviewed the papers concerned with the chemistry of electronically excited complexes which afford numerous examples of compounds accessible at best with difficulty by other routes, and commented on the papers.View full abstractDownload PDF (1337K) -
Kazuhiro NAKASUJI1985 Volume 43 Issue 2 Pages 145-152
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSA feature of phenalenyl system arises from the stability of three redox states, cation, radical, and anion, each of which is characterized by the number of electrons occupied in a NBMO. Although a wide range of phenalenyl chemistry have already been explored, the phenalenyl still plays a unique role in search for theoretically interesting molecules. This review is concerned with the new aspects of phenalenyl chemistry which are related to 1) the properties of the cation and the anion, 2) the utilization in organometallic compounds as a ligand, 3) the design of multistage redox systems, 4) the extension to the heterocycles containing thiadiazine skeleton.View full abstractDownload PDF (1076K) -
Shinsaku FUJITA1985 Volume 43 Issue 2 Pages 153-166
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSSyntheses, structures, and reactions (reductions, 1, 4-additions, hydrolyses, Diels-Alder additions, reactions with aromatic compounds, Grignard reagents, amines, sulfonylchloramides, phosphorus compounds, active methylene compounds, enamines, diazoalkanes, etc.) of the title compounds are reviewed. Their applications to color photography are also described.View full abstractDownload PDF (1292K) -
Toshio ISHIKAWA1985 Volume 43 Issue 2 Pages 167-175
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe background and main points of recent works on vapor phase oxidation of C3, C4 olefins and ethylbenzene with multi-component oxide catalysts are described.
Fe-As and Mo-Ce (or Al, Ba, Sr) -As oxides were found to have high catalytic activity for producing acrolein by vapor phase oxidation of propylene with air. The activity of Fe-As oxide decreased with reaction time because of the escape of As component, especially in the reaction at high temperature, such as oxidation of i-butylene to methacrolein.
This defect was eliminated and initial activity was kept by adding Li component to Fe-As system. With Fe-Li-As oxide of atomic ratio= 1 : 2 : 2.5 1 : 3 : 3, high yield of methacrolein was obtained from i-butylene at the temperature of 470°C.
By means of searching direct oxidation of the olefins with Fe-As5+ oxide systems and formation of As5+ in As3+ oxide systems and studying the structure of catalyst, following conclusions were obtained.
The catalytic oxidation of α-CH bond to aldehyde is carried out by a cycle consisting of two reactions :
2 As5+ oxide + CH2 = CR-CH3 → 2 As3+oxide CH2= CR-CHO and
2 As 3+oxide + O2 → 2 As5+oxide (R : H or -CH 3).
The former reaction, remarkably promoted by the Fe component in the catalyst, is always accompanied with formation of CO2, but proceeds more dominantly when As5+ concentration is high. Two structures of -Fe-O-As- and -Li -O-As- were observed in Fe-Li-As oxide catalyst; the former is more easily reduced with olefin than the latter.
-Fe-O-As- structure has at least two kinds of active site. Unsaturated aldehyde forms on one site and CO2 on another site. Li-O-As structure is stable and instrumental in preventing the escape of As component into vapor phase.
The activity of Mo-X-As (X : alkaline earth metal) oxide catalyst for oxidative dehydrogenation of 1-butene was studied in connection of its preparation and physical property.
A Si-Ce-Sb oxide catalyst of new type showed relatively high activity for styrene formation by oxidative dehydrogenation of ethylbenzene.View full abstractDownload PDF (1001K) -
Kozaburo NISHIYAMA1985 Volume 43 Issue 2 Pages 176-179
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe efficient introduction of nitrogen atom or azido group to organic molecules is important in amino derivatives or heterocycle synthesis. Most of attentions on silyl azides have been hitherto focused on their properties and heterocycle synthesis. In this article, trimethylsilyl azide (TMSA) is widely shown as a synthetic reagent, including azide formation. Trimethylsilymethyl azide (TMSMA), which is regarded as a silylated derivative of methyl azide, is also shown as such a new reagent. The advantage of using these azides in organic synthesis is presented.View full abstractDownload PDF (399K) -
Yoshiaki TAKAGI1985 Volume 43 Issue 2 Pages 180-181
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSDownload PDF (174K) -
Sousuke YAMANE1985 Volume 43 Issue 2 Pages 182-183
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESS -
[in Japanese], [in Japanese], [in Japanese]1985 Volume 43 Issue 2 Pages 184
Published: February 01, 1985
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSDownload PDF (143K)
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