Abstract: A process for preparing 2-alkynoic esters of the general formula (I),R.sup.1 --O--CO--C.tbd.C--R.sup.2 (I)in which R.sup.1 and R.sup.2 independently are C.sub.1-16 -alkyl, C.sub.6-12 -aryl, C.sub.7-12 -aralkyl or C.sub.7-12 -alkylaryl radicals, and R.sup.2 can also be hydrogen,by reacting a chloroformate of the general formula (II),R.sup.1 --O--CO--Cl (II)with an alkyne of the general formula (III),R.sup.2 --C.tbd.C--H (III)is carried out in the presence of a Pt and/or Pd complex which has phosphine ligands and/or phosphite ligands as catalyst.

Abstract: Polymeric UV absorbers based on the units shown in the schematized formula I ##STR1## where the sequence of the units is arbitrary, the sum of a+b+c+d=100 anda is a value from 5 to 95,b is a value from 0 to 70,c is a value from 5 to 95,d is a value from 0 to 70and the radicals R have the meaning explained in the description, are described.

Abstract: Dyes of the formulaQ-X=HetwhereX is nitrogen or CH,Q is a 5- or 6-membered carbocyclic or heterocyclic radical and Het is a radical of the formula ##STR1## where Y is oxygen, sulfur, imino, C.sub.1 -C.sub.4 -alkylimino, substituted or unsubstituted phenylimino or the radical of an acidic-CH compound, A is oxygen or a radical of the formula C--U, where U is as defined in the description part, and E --is oxygen, sulfur, selenium, imino, C.sub.1 -C.sub.4 -alkylimino or substituted or unsubstituted phenylimino,are useful for thermal transfer and for dyeing or printing synthetic materials.

Abstract: A process for the preparation of butyrolactones of the formula I ##STR1## where the substituents R.sup.1 and R.sup.2 are hydrogen, alkyl or hydroxyalkyl groups, or aryl and trialkylsilyl groups, if appropriate carrying inert: substituents, is described in which an alkyne of the formula IIR.sup.1 --C.tbd.C--R.sup.2 IIwhere the substituents have the meanings indicated above, is reacted under reducing conditions at elevated pressure and elevated temperature with carbon monoxide CO and hydrogen in the presence of a transition metal catalyst or with carbon monoxide and water in the presence of a transition metal catalyst.

Abstract: A process for preparing N-alkyl-substituted aminoalkynes by reacting an alkyne with a carbonyl compound and an amine with heterogeneous catalysis in which an unsupported copper acetylide derived from malachite is used as the catalyst. The N-alkyl-substituted aminoalkyne have a wide variety of uses including their use as precursors for pharmaceuticals, their use in electroplating processes and their use as corrosion inhibitors.

Abstract: N-Hydroxyalkyl-substituted aminoalkynes of the formula I ##STR1## are prepared by reacting an alkyne with a 1-oxa-3-azaheterocyclo-alkane in a reaction with heterogeneous catalysis by a catalyst which comprises a compound of a metal of the first or second sub-group.

Abstract: Hydroxyalkyl-substituted aminoalkynes of the general formula I ##STR1## where at least one of the substituents R.sup.1, R.sup.4 or R.sup.5 is hydroxyalkyl are prepared in a reaction with heterogeneous catalysis.