5-formyl-2,3-dihydroxybenzonitrile

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 1.35 g of 2,3-dihydroxybenzonitrile and 1.4 g of hexamethylene tetramine in 20 ml of trifluoroacetic acid was refluxed for 1.5 h. Water was added and the product was filtered. Yield 0.9 g (55%), m.p. 211°-215° C. was refluxed for 1.5 h the product was filtered

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 1.35 g of 2,3-dihydroxybenzonitrile and 1.4 g of hexamethylene tetramine in 20 ml of trifluoroacetic acid was refluxed for 1.5 h. Water was added and the product was filtered. Yield 0.9 g (55%), m.p. 211°-215° C. was refluxed for 1.5 h the product was filtered

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 18 g of the product of Step A and 400 ml of dichloromethane were mixed together under nitrogen and the mixture was cooled to 0° C. 150 ml of a molar solution of boron tribromide in dichloromethane were added and the mixture stood for one night at ambient temperature. It was concentrated, cooled again to 0° C. and 250 ml of a normal solution of hydrochloric acid were added. The crystallized product was separated out, washed with water, dried then crystallized from an isopropanol-water mixture (1-2) to obtain 12 g of the expected product. the mixture stood for one night at ambient temperature It was concentrated cooled again to 0° C. 250 ml of a normal solution of hydrochloric acid were added The crystallized product was separated out washed with water dried then crystallized from an isopropanol-water mixture (1-2)

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 0.61 g of rhodanine, 0.72 g of 3,4-dihydroxy-5-cyanobenzaldehyde and 0.1 ml of piperidine in 10 ml of acetic acid was heated for 4 h at 100° C. The product was filtered and washed with 2-propanol. Yield 0.35 g, mp >350° C. The product was filtered washed with 2-propanol

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 0.58 g of thiohydantoin, 0.82 g of 3,4-dihydroxy-5-cyanobenzaldehyde and 0.1 ml of piperidine in 10 ml of acetic acid was heated for 4 h at 100° C. The product was filtered and washed with ether. Yield 0.51 g, mp 210°-213° C. The product was filtered washed with ether

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 0.58 g of thiohydantoin, 0.82 g of 3,4-dihydroxy-5-cyanobenzaldehyde and 0.1 ml of piperidine in 10 ml of acetic acid was heated for 4 h at 100° C. The product was filtered and washed with ether. Yield 0.51 g, mp 210°-213° C. The product was filtered washed with ether

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 18 g of the product of Step A and 400 ml of dichloromethane were mixed together under nitrogen and the mixture was cooled to 0° C. 150 ml of a molar solution of boron tribromide in dichloromethane were added and the mixture stood for one night at ambient temperature. It was concentrated, cooled again to 0° C. and 250 ml of a normal solution of hydrochloric acid were added. The crystallized product was separated out, washed with water, dried then crystallized from an isopropanol-water mixture (1-2) to obtain 12 g of the expected product. the mixture stood for one night at ambient temperature It was concentrated cooled again to 0° C. 250 ml of a normal solution of hydrochloric acid were added The crystallized product was separated out washed with water dried then crystallized from an isopropanol-water mixture (1-2)

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 18 g of the product of Step A and 400 ml of dichloromethane were mixed together under nitrogen and the mixture was cooled to 0° C. 150 ml of a molar solution of boron tribromide in dichloromethane were added and the mixture stood for one night at ambient temperature. It was concentrated, cooled again to 0° C. and 250 ml of a normal solution of hydrochloric acid were added. The crystallized product was separated out, washed with water, dried then crystallized from an isopropanol-water mixture (1-2) to obtain 12 g of the expected product. the mixture stood for one night at ambient temperature It was concentrated cooled again to 0° C. 250 ml of a normal solution of hydrochloric acid were added The crystallized product was separated out washed with water dried then crystallized from an isopropanol-water mixture (1-2)

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 18 g of the product of Step A and 400 ml of dichloromethane were mixed together under nitrogen and the mixture was cooled to 0° C. 150 ml of a molar solution of boron tribromide in dichloromethane were added and the mixture stood for one night at ambient temperature. It was concentrated, cooled again to 0° C. and 250 ml of a normal solution of hydrochloric acid were added. The crystallized product was separated out, washed with water, dried then crystallized from an isopropanol—water mixture (1-2) to obtain 12 g of the expected product. the mixture stood for one night at ambient temperature It was concentrated cooled again to 0° C. 250 ml of a normal solution of hydrochloric acid were added The crystallized product was separated out washed with water dried then crystallized from an isopropanol—water mixture (1-2)