20-tetra-m-tolyl-, or 5,10,15,20tetra-p-tolyl-porphyrinate(2-); X = N, or SCN] have been prepared. The stereochemistry of the metal has been established by i.r. and l H n.m.r. measurements and confirmed by the crystal structure determination of the title compound by X-ray diffraction methods using Cu-K, radiation. Crystals are monoclinic, space group P2,/c, with a = 13.469(1), b = 13.497( 1 ), c = 19.050(2) A, p = 106.28( 1 ) O , and 2 = 4; R ( F ) = 0.041, R ' ( F ) = 0.044 for 6 295 reflections. The gallium atom is five-co-ordinated by the four nitrogen atoms ( NP) of the porphyrin plane and one nitrogen atom N(5) of theazidogroup: mean Ga-N, 2.034(3), Ga-N(5) 1.955(2) A, N(5)-Ga-NP 100.3(10), Ga-N(5)-N(6) 120.8(1)". Recently hydrocarbon oxidations with oxometalloporphyrinates have been investigated extensively. '-' According to a ate(2-), tmtp = 5,10,15,20-tetra-rn-tolyiporphyrinate(2-), tptp = 5,10,15,20-tetra-p-tolylporphyrinate(2 -).J.