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A novel and efficient lanthanum metal-assisted carbon-carbon bond formation of diaryl ketones and various electrophiles, such as carbonyl compounds, esters, nitriles, and epoxides, has been developed. When diaryl ketones were allowed to react with dialkyl ketones in the presence of lanthanum metal and a catalytic amount of iodine, the cross pinacol coupling reaction proceeded to give the corresponding unsymmetrical 1,2-diols in moderate to good yields. α-Hydroxy ketones were prepared by the lanthanum metal-assisted reaction of diaryl ketones with esters or nitriles, followed by hydrolysis with aq HCl. It is interesting to note that for the epoxides, the coupling reaction proceeded via the Meinwald rearrangement of epoxides to give the corresponding 1,2-diols.

A novel and efficient lanthanum metal-assisted carbon-carbon bond formation of diaryl ketones and various electrophiles, such as carbonyl compounds, esters, nitriles, and epoxides, has been developed. When diaryl ketones were allowed to react with dialkyl ketones in the presence of lanthanum metal and a catalytic amount of iodine, the cross pinacol coupling reaction proceeded to give the corresponding unsymmetrical 1,2-diols in moderate to good yields. α-Hydroxy ketones were prepared by the lanthanum metal-assisted reaction of diaryl ketones with esters or nitriles, followed by hydrolysis with aq HCl. It is interesting to note that for the epoxides, the coupling reaction proceeded via the Meinwald rearrangement of epoxides to give the corresponding 1,2-diols.

During the time of the prewar international gold standard, Japan had issued large amounts of external bonds, mainly in London and New York financial markets, as the balance of Japanese external bonds issued peaked in 1930 at JPY2,268 million, accounting for about 15 % of Japan’s estimated GNP. But Japan’s access to raising such bonds was closed off by the Great Depression and the collapse of the international gold standard. After the end of World War II and 6 years of occupation led by the General Headquarters, Supreme Commander for the Allied Powers (GHQ/SCAP), Japan regained independence in April 1952 and joined the IMF and the World Bank in August of that year. Japan’s participation in the Bretton Woods system had been realized with the strong support of the U.S. government, which had desired an independent Japanese economy after a turnabout in its postwar policies toward Japan. At that time, expectations had risen in Japan that this would open a path toward access to foreign capital for purposes of economic restoration and development in place of American aid. While its participation in the Bretton Woods system enabled Japan to raise long-term funds from the World Bank, to do so it needed to resolve the issue of repayment of outstanding prewar external debts on which it effectively had defaulted during World War II. In July 1952, a conference on resolution of these debts was held in New York between the Japanese government and representatives of British, French, and the United States’ bondholders under the terms of the San Francisco Peace Treaty, and an agreement was reached in September of that year, under which Japan resumed payment on nearly all government bonds, not including those issued in France. The success of negotiations on resolution of external debts was important in that it meant Japan had regained the trust of international society and served as the starting point for Japan’s postwar access to foreign capital.

安息香酸ビニル (I), α-ナフトエ酸ビニル (II), トリフェニル酢酸ビニル (III), p-クロロ安息香酸ビニル (IV), 2, 4-ジクロロ安息香酸ビニル (V), ヘキサヒドロ安息香酸ビニル (VI), トリメチル酢酸ビニル (VII), およびジクロロ酢酸ビニル (VIII) を, 主として酢酸ビニルと相当するカルボン酸とのエステル交換反応により製造した。(V) は新モノマーであり, その融点は38～40℃, 沸点は105～110℃/4mm Hgである。(VI) の沸点は115℃/3mm Hgであるという報告があるが, これは誤りであり, 62～69℃/5mm Hgであることを認めた。これらのモノマーをAIBNを開始剤に用いて, 主として60℃で塊状重合した。(III) からはポリマーがほとんど得られず, (II) からもわずかのポリマーしか得られなかったが, その他のモノマーからは高収率でポリビニルエステルが得られた。(IV), (V), (VI), (VII), (VIII) の重合速度は同程度であり, (I) の重合速度はこれらよりかなり小さかった。いずれのモノマーの場合にも, 生成ポリマーの分子量は重合率の上昇に伴って増大し, ある場合には不溶性のポリマーが生じた。これらの結果に対して少し議論した。