NOVELTY - A metal complex is prepared by providing a 1-monoacyldipyrromethane and combining with a boron compound.    USE - For making 1-monoacyldipyyrromethane-boron complexes and 1-acyl-9-substituted dipyrromethane boron complexes useful as intermediates for porphyrinic compounds such as porphyrins, chlorins, corroles and bilanes.    ADVANTAGE - Unlike prior art processes, the method avoids chromatography and facilitates purification by providing complexes in crystalline form, enabling synthesis of 1-acyldipyrromethanes at multigram scale and providing increased scale of porphyrin synthesis.    DETAILED DESCRIPTION - Making a metal complex involves providing a 1-monoacyldipyrromethane and combining with a boron compound of formula R1R2MX to give a metal complex of formula DMR2 (sic).    M=B;    R1, R2=alkyl, alkenyl, alkynyl or aryl (optionally substituted by alkyl, alkenyl, alkynyl, aryl, alkoxy, alkylcarbonyl, alkylcarbonyloxy, alkylsulfinyl, alkylsulfonyl, alkylthio, halo, cyano, nitro, sulfo, oxo, formyl, azido, or carbamoyl);    X=anion leaving group;    DH=1-mono-acyldipyrromethane.    N.B. R is not defined in the claims. In the disclosure, R2B may be Bu2B, Me2B, 9-BBN (9-borabicyclo(3.3.3.1)nonane) of formula (a), F2B or B-catechol of formula (b).    INDEPENDENT CLAIMS are also included for the following:    (A) a method of making a 1,9-diacyldpyrromethane metal complex comprising providing a 1-monoacyldipyrromethane-boron complex; and acylating the 1-monoacyldipyrromethane in the complex at the 9 position to produce 1,9-diacylpyrromethane metal complex;    (B) a method for making a compound useful as a chlorin eastern half, comprising providing 1-monoacyldipyrromethane-boron-complex; and substituting the boron complex at the 9 position with halo, alkoxy, or acetoxy to produce a 1-acyl-9-substituted dipyrromethane boron complex;    (C) a 1-monoacyldipyyrromethane-boron complex of formula DMR1R2 in solid or crystal form;    (D) making a porphyrin by providing a 1-monoacyldipyrromethane-boron complex, and reducing the 1-mono-acyldipyrromethane in the complex without prior decomplexation of the boron to produce the porphyrin.