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The [2 + 2]cycloaddition of phenyl isocyanate to 2,3-dihydrofuran was appreciably accelerated by compression to produce a β-lactam ring; its apparent activation volume was estimated to be −28 ml mol−1. Similar β-lactams were obtained under high pressure in the reaction of phenyl isocyanate with various vinyl ethers. Although the [2 + 2]cycloaddition of alkyl isocyanates to 2,3-dihydrofuran was also accelerated under high pressure to give β-lactams with good yields; the reactions of alkyl isocyanates with ethyl vinyl ether were slow, even at high pressure.

The desulfurization-condensation reaction was investigated in the presence of silver(I) salt for several kinds of thiocarbonyl compounds with nucleophiles. Such thiocarbonyl compounds as 4,4′-bis(dimethylamino)thiobenzophenone, ethylene trithiocarbonate, and N-(thiobenzoyl)morpholine react with malononitrile or other active methylene compounds in the presence of silver trifluoroacetate to afford the corresponding olefinic compounds together with silver sulfide. This reaction of thiocarbonyl compounds with some other nucleophiles, such as aniline derivatives and ethylene glycol, has also afforded imines and 1,3-dioxolane derivatives.

ビリジンの存在下,トルエン溶媒中でフェニルイソシアナートを高圧下に反応させると主成分として二量体である1,3-ジフェニル-1,3-ジアゼチジン-2,4-ジオンが高収率で得られた.この反応は大きな圧力効果を示し,30℃ におけるみかけの活性化体積は-23ml/molと計算された.3-メチルピリジンおよび4-メチルピリジソはピリジンよりもさらに高い触媒活性を示したが,2-メチルピリジン,2,6-ジメチルピリジンはほとんど触媒活性を示さず,ビリジン環の窒素のまわりのかさ高さが触媒能に大きく影響した.圧力を上げたり,ピリジン触媒の量を増やすと二量体の選択性が向上したが,トリエチルアミソのような脂肪族アミン触媒を用いたり,アセトニトリルなどの極性溶媒中の反応では三量体が主成分となった.二量体の生成機構として四員環遷移状態を経由する機構を推定した.高圧下の反応により,衡またはか位に匿換基を有するフェニルイソシアナートでは好収率で二量体が得られるが,ゲクロロフェニル,1-ナフチル,及びアルキルイソシアナート類では二量化が進行しなかった.

5,6-Dihydro- 1,3,5-trimethyl-6-methylimino-1,3,5-triazine-2,4-(1H,3H)-dithione (1) was synthesized by the reaction of methyl isothiocyanate under high pressure in the presence of Et3N and H2O. The yield and selectivity of 1 were seriously effected by pressure, reaction temperature, solvent, and the amount of H2O.

S-チオカルバモイル,S-アロイル,および8-(N-フニニルベンズイミドイル)チオヒドロキシルアミン類におけるアミノ基の反応性に注目し,安息香酸無水物によるベンゾイル化とベンズアルデヒド類によるイミン化合物の生成について検討した。これらのチオヒドロキシルアミン類はいずれも,熱および酸に対してやや不安定であるにもかかわらず,比較的に穏和な条件で対応するN-ベンゾイル誘導体および一連の薪規なイミン誘導体が,かなりよい収率で得られた。このことから,これらの化合物のアミノ基はアミン類ほどの活性はないものの,アミド類のものよりも高い活性を有しているものと考えられた。3-チオカルバモイルチオヒドロキシルアミンとアルデヒドとから誘導されるイミン化合物は銀イオンに対して特異的な親和性を示し,銀塩と1:1の付加体を生成することも見いだした。

The ring expansion reactions of 1,3-oxathiolium salts (1) using NaN3 and an I2–aq NH3 system resulted exclusively in the formation of 1,4,2-oxathiazines (3) by incorporation of a nitrogen atom into the C–O bond in 1. On the other hand, the reaction of 1 with dialkylamino(thioxo)methanesulfenamides, another type of N-expansion reagent, gave di-5-thiazolyl sulfide derivatives (4) in addition to 3. The structure of 4 was confirmed by X-ray crystallographic analysis. It was speculated that the formation of 4 goes via initially-formed 3. Furthermore, 1 reacted with another N-unsubstituted sulfenamides having a heterocyclic substituent such as a 2-pyridyl and 2-benzothiazolyl group to afford 2-pyridyl 5-thiazolyl sulfide and 2-benzothiazolyl 5-thiazolyl sulfide derivatives, respectively, together with 3. The stability and reactivity of oxathiazines 3, which comprise an electron-rich π-system, were also examined.

トリエチルアミンの存在下,ベンゼン溶媒を用いてイソチオシアン酸メチルを800MPa,100℃ で20時間反応させると三量体である1,3,5-トリメチル-1 ,3,5-トリアジソ-2,4,6(1H,3H,5H)-トリチオンが高収率で得られた。同じ反応を常圧で行っても三量体はまったく生成せず,この反応が高圧力下で大きく促進されることが明らかになった。第三級アルキルアミンはみな高い触媒活性を示したが,フェニル基のついたN,N-ジメチルアニリンは活性を示さなかった。ピリジンは高い触媒活性を示したが,2-位にメチル基のついた2-メチルピリジン,2,6-ジメチルピリジンは活性がなく,窒素のまわりのかさ高さが触媒能に大きく影響した。イソチオシアソ酸エチルはメチルエステルと同様な条件で三量体を高収率で与えたが,より錬長の長いアルキル基をもつイソチオシアン酸プロピルおよびブチルでは,そのような条件では反応性が低く,三量体は低収率であった。しかしDBU触媒を用い,130℃ に温度を上げることによりこれらのイソチオシアソ酸エステルにおいても好収率で三量体が得られた。分子内に二重結合を持つイソチオシアン酸アリルでは,DBU触媒を用いたり高温では重合が優先したが,トリエチルアミン触媒を用い,圧力を1200MPaまで上げることにより娃収率で三量体が得られた。

At 800 MPa, 130 °C carbon oxide sulfide condensed with dialkylcyanamide to afford 2,6-bis(dialkylamino)-1,3,5-thiadiazin-4-ones in good yields.

The trimerization of phenyl isocyanate in the presence of triethylamine was accelerated under high pressure to give triphenyl isocyanurate almost quantitatively. The reaction in benzene was remarkably accelerated by compression. The effects of pressure, temperature, catalysts, and solvents were examined on the trimerization of phenyl isocyanate. Aryl and normal alkyl isocyanates trimerized under high pressure to give the corresponding isocyanurates in good yields, whereas isocyanates having bulky alkyl groups such as t-butyl and cyclohexyl did not trimerize even under 800 MPa.

S-Thioaroylsulfenamides (ArCSSNH2), formed by reaction of ArCSS−Na+ with hydroxylamine-O-sulfonic acid, were aroylated or acylated to give N-aroyl- or N-acyl-S-thioaroylsulfenamides, respectively, which were then cyclized with dehydration to afford 3-substituted 5-aryl-1,4,2-dithiazolium salts. The behavior of 3,5-diphenyl-1,4,2-dithiazolium perchlorate toward nucleophiles such as active methylene and amino compounds was studied systematically. The reaction can be classified into two cases depending on fission modes of initial adducts, i.e., ring opening–ring closure reaction (Path B) and fragmentation of dithiazole ring (Path C), and in some cases the initial adducts were isolated.

N-(Substituted formyl)dialkylamino(thioxo)methanesulfenamides (R2NCSSNHCOR′ 3: R = alkyl, R′ = alkyl, dialkylamino, alkoxy, and heterocyclic substituent) were treated with a strong acid (HBF4 or HClO4) in Ac2O to afford 1,4,2,-dithiazolium salts (7) and/or 3,5-bis(dialkyliminio)-1,2,4-trithiolanes (9). The reactivity is markedly dependent on the nature of substituents (NR2 and R′) and the acid used. For R′ = MeO, the sulfenamides reacted successively with NaH and p-toluenesulfonyl chloride to give methyl bis(dialkylthiocarbamoylthio)carbamates (10). The mechanisms for the formation of 9 and 10 are discussed.

N-(Substituted formyl)dialkylamino(thioxo)methanesulfenamides (R2NCSSNHCOR′, 2), anti-foggants for silver halide photographic materials as well as potential precursors for 1,4,2-dithiazolium salts, were prepared in good yields in two “one-pot” procedures. Various amide-type compounds (R′CONH2, 1) were treated successively with NaH and I2 and then condensed with dialkyldithiocarbamates (Method A); or 1 were reacted with tetraalkylthiuram disulfides after treatment with NaH (Method B). These methods allowed a wide variation of substituents R′ in 2: R′=H, dialkylamino, alkoxy, aryl, alkyl, and heterocyclic substituent.

The title reaction at 800 MPa, 70 °C, give 5-imino-1,4,2-dithiazoles, formed through 1,3-dipolar cycloaddition. These adducts decompose to the reactants on heating at ambient pressure. At 160 °C and 800 MPa, the reaction give thermally stable [1,2,4]dithiazolo[1,5-b][1,2,4]dithiazole-6a-SIV derivatives.

Three potential biosynthetic intermediates for aminocyclitol antibiotics, neosamine C-CDP, -UDP, and -ADP, have been synthesized from D-glucosamine by chemical means. 2,6-Diamino-2,6-dideoxy-α-D-glucopyranosyl phosphate, derived from the corresponding glycosyl bromide, was condensed with three nucleosides (CMP, UMP and AMP) by a known procedure. The configurations of the neosamine C nucleoside diphosphates have been confirmed by 13C NMR spectra.

The reaction of 3-aryl-5-benzoyl-2-imino-2,3-dihydro-1,3,4-thiadiazoles (6) with dimethyl acetylenedicarboxylate (4b) gave the corresponding thiazole (8) and benzoyl cyanide through sulfurane (B) by 1,3-dipolar cycloaddition and cis- (9) and trans-vinyl (10) compounds through zwitterion (C) by simple addition. Two types of addition reactions competed each other and the ratio of the two [R=B/C] depended solely on the solvent polarity (ET). Dibenzoylacetylene behaved similarly. Several iminothiazolines and iminothiadiazolines reacted with activated acetylenes and the selectivity for the two types of addition reactions for each system was shown to be affected by quite subtle balance of electron-withdrawing ability of each heterocycle.

Cyclic voltammetry of seven substituted benzoylsilanes (1) and three benzoylgermanes (2) were investigated. The effects of substituents of 1 and 2 on both cathodic reduction and anodic oxidation potentials were discussed. The cathodic reduction products of 1 were also examined.

シクロヘキシルベンゼン(CHB)の酸素酸化/酸分解反応を無触媒および臭化水素触媒存在下で検討した。無触媒時の自動酸化では,生成物の1-フェニルシクロヘキシルヒドロペルオキシド(PCP)の選択率は,温度あるいは酸素圧にかかわりなく,もっぱら原料転化率によって決まり,実際的な反応温度範囲の90～140℃では,CHB転化率40%でPCP選択率80%であった。クメンの自動酸化では考慮する必要のなかった,第二級炭素上からの水素の引き抜きもCHBでは無視できない。臭化水素存在下では,反応は常圧下室温以下で酸素供給律速で進みフェノールとシクロヘキサノンが主生成物であった。フェノールを産出する特異な酸素酸化であるが,ベンゼンジオールによって完全に阻害されるなどの特徴から,この反応がラジカル過程で進むことが明らかになった。臭化水素は反応開始剤およびBrラジカルの供給源となり,このBrラジカルがCHBからの水素引き抜き剤として働くため,反応は無触媒時にくらぺ圧倒的に速く進むと考えられる。CHB転化率は仕込みHBr量に依存し,-8℃ から30℃ではO2/HBr=3.2の比率で酸素が吸収された。ところがHBr濃度が一定値を超えると反応が阻害される臨界現象が現われた。トリフルオロ酢酸をHBrとともに用いることにより,臨界現象はもっぱら酸濃度に依存することが明らかになり,生成物から副生する阻害剤に起因すると推定された。HBrはCHBの酸素酸化にきわめて有効な触媒であると結論された。

The oxidation of phenol with peracetic acid has been investigated in connection with the industrial preparation of benzenediols. The effects of 25 additives, such as derivatives of monomeric and condensed phosphoric acid, chelating agents, and salts of polybasic carboxylic acids, were examined; derivatives of condensed phosphoric acid were found to be most effective. The oxidation of phenol (213 mmol) with peracetic acid (21 mmol) in the absence of the additives gave 1,2- and 1,4-benzenediols in only 5.8% and 7.6% yields, respectively. But in the presence of 2.0×10−7 mol of potassium diphosphate the yields of 1,2- and 1,4-benzenediol were 47% and 31%, respectively. The improvement in the yields by the additives is attributable to the masking of a trace of metals, especially iron and cobalt, present in the reaction mixture. These metals tend to catalyze the further oxidation of the benzenediols formed.

The structure of the 1:1 adduct of “Hector’s base” with arylcyanamides was determined by X-ray analysis of tris-p-bromophenyl derivative (1a). The molecule is almost planar and the strong interaction was exemplified between the sulfur and the nitrogen atoms.

Photolysis of 5-nitrosoimino-4-phenyl-3-phenyliraino-1,2,4-thiadiazolidine proceeded through π-π* excitation and gave phenylcyanamide and 5-imino-4-phenyl-3-phenylimino-1,2,4-thiadiazolidine as primary products. It was found that other products were produced by the reactions of the primary products. The formation mechanisms have been discussed briefly.

Correlations of ionization potentials and electrochemical oxidation potentials for group 4B dimetals were obtained.