Reductive carbonylation of gem-dibromocyclopropanes was achieved by treatment with tetracarbonylnickel in the presence of alcohols, amines, thiols, or imidazole in DMF leading to the corresponding cyclopropanecarboxylic acid derivatives, respectively. Use of disulfides as an initial nucleophile resulted in carbonylation with sulfenylation at the geminal position. This method was applied to the intramolecular reductive carbonylation reaction of 2,2-dibromocyclopropanealkanols into bicyclic lactones. Nickel carbenoid and enolate complexes are assumed to be involved as key intermediates.

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A method is proposed for soil improvement of salt-affected soils to till down to about 600 mm in depth by a special plough. The goal is to cut off the capillary rise of the groundwater by creating a coarse layer of tilled subsoil.Earlier, a plough configuration to produce soil clods with the proper size in the subsoil was determined in an indoor soil bin. In this paper, we designed and tested prototypical plough bodies in field experiments. A plough blade length less than 130 mm produced large soil clods and a blade length more than 130 mm generated small ones.With any length, deeper operating depth caused larger soil clods to form. The proper specifications of the third and fourth plough bodies of the special plough are as follows: the plough blade length is 130 mm, the operating width is 300 mm, the operating depth is 200 mm and the cutting angle is 20°.

Reductive Carbonylation of the gem‐dibromocyclopropanes (I) is achieved by treatment with tetracarbonylnickel (IV) in the presence of the amines (II), the alcohols (V), imidazole (VII) and the thiols (IX) leading to the cyclopropanecarboxylic acid derivatives shown in the scheme.

Aus den l,l ‐Dibrom‐cyclopropanen (I) erhält man mit Alkoholen und Aminen (II) in Gegenwart von Nickeltetracarbonyl die entsprechenden Carbonsäurederivate (III) über diskutierte Zwischenstufen.