Otto Roelen discovered the 0x0 syn-catalysts. but with no knowledge what-fering mentalities of two difficult personthesis (hydroformylation) in 1938, and soever of their potential application. Hy-alities. In less turbulent times these two despite all the problems created by the droformylation today constitutes one of unpredictable individuals might well war ycars he was able to explore success-the most important industrial examples have collaborated. A number of confully the fundamental aspects related to of a homogeneous catalytic process.temporary documents published here its application up to the point of building A unique opportunity for academic for the first time, supplemented by the first plant. At the same time he laid and industrial chemists to engage in a Allied reports related to "hidden reparathe groundwork for industrial utilizagoal-oriented collaborative effort with tions," provide interesting insights into tion of homogeneous organometallic respect to an important new synthetic the nature of this particular discovery catalysts. Almost simultaneously. his method was missed in this case, how-and its subsequent course of developcontemporary, Walter Hieber, was inves-ever-missed less as a consequence of ment. tigating the basic chemistry of the same events of the day than because of the dif-L