Rothemund reaction

The Rothemund Reaction is useful for making substituted porphines (seen in examples on next page) ... 

Inverted porphyrin or 2-aza-21-carbaporphyrin 88 also known as an NCP (Figure 3) was first isolated as a by-product of normal acid-catalyzed condensation of pyrrole and benzaldehyde (1994ACI779, 1994JA767). Latos-Grazynski and coworkers employed a Rothemund reaction between tolualdehyde and pyrrole in the presence of BF3-Et20 in DCM, followed by oxidation with 2,3,5,6-tetrachloro-p-benzoquinone (chloranil) to obtain NCP (1994ACI779). Simultaneously, Furuta and coworkers also reported... 

Furuta et al. have reported the synthesis of an N-fused normal 22it-electron pentaphyrin containing a fused tripentacyclic ring from the Rothemund reaction of an aldehyde and a pyrrole using BF3 Et20 and DDQ (Scheme 57) (01ACI619). 

Rothemund reactions. Preparation of meso-tetrasubstituted porphyrins by condensation of pyrrole with an aldehyde. 

Paolesse R, Mini S, Sagone F, Boschi T, Jaquinod L, Nurco DJ, Smith KM (1999) 5,10,15-triphenylcorrole a product from a modified rothemund reaction. Chem Commun 14 1307-1308... 

The well-known Rothemund reaction for the synthesis of 5,10,15,20-tetrasubstituted porphyrins 29 from aromatic or heteroaromatic aldehydes and pyrrole has the disadvantage of producing a large quantity of side products such as polypyrrole, linear condensation products and chlorines. Therefore, no... 

Other references related to the Rothemund reaction are cited in literature. 

Robinson Annulation Robinson-Schopf Reaction Rosenmund Reduction Rosenmund-von Braun Synthesis Rothemund Reaction Rubottom Oxidation Ruff-Fenton Degradation Rupe Rearrangement Ruzicka Large Ring Synthesis Sabatier-Senderens Reduction Sachs (see Ehrlich-Sachs Reaction)... 

Porphyrins and their analogs are highly diverse in their structure and thus need specific synthetic methodologies for each class of porphyrinoids. Different approaches are followed to synthesize -substituted, meso-substituted, and other complex modified ring systems. Of all the schemes, the Rothemund reaction of pyrrole and aryl aldehyde in refluxing propionic acid to yield meso-substituted porphyrin (e.g., 36) is the simplest and a very common method (Scheme 9.3)... 

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