In 1832, the German chemist Johann Wolfgang D?bereiner ,first isolated furfural ,he formed a very small quantity of it as a byproduct of formic acid synthesis. 
In 1840, the Scottish chemist John Stenhouse found that the same chemical could be produced by distilling a wide variety of crop materials, including bran, corn, oats, and sawdust, with aqueous sulfuric acid, and he determined that this chemical had an empirical formula of C₅H₄O₂. 
In 1901, the German chemist Carl Harries deduced furfural's structure.

NTP Carcinogenesis Studies (gavage); Clear Evidence: mouse NCITR*    National Cancer Institute Carcinogenesis Technical Report Series. (Bethesda, MD 20014) No. NTP-TR-382,90, . , Some Evidence: rat NCITR*    National Cancer Institute Carcinogenesis Technical Report Series. (Bethesda, MD 20014) No. NTP-TR-382 ,1990. . EPA Genetic Toxicology Program. Reported in EPA TSCA Inventory.

OSHA PEL: TWA 2 ppm (skin)
ACGIH TLV: TWA 2 ppm (skin); Animal Carcinogen: BEI: 200 mg/g creatinine of total furoic acid in urine at end of shift
DFG MAK: Confirmed Animal Carcinogen with Unknown Relevance to Humans
DOT Classification:  3; Label: Flammable Liquid

For occupational chemical analysis use OSHA: #ID-72 or NIOSH: Furfural, 2529.

Furfural is an heterocyclic aldehyde, with the ring structure shown at right. Its chemical formula is OC₄H₃CHO. It is a colorless oily liquid with the odor of almonds, but upon exposure to air samples quickly become yellow. With the CAS NO. 98-01-1, Furfural dissolves readily in most polar organic solvents, but is only slightly soluble in either water or alkanes. When heated above 250 °C, furfural decomposes into furan and carbon monoxide, sometimes explosively.

Physical properties Furfural are: 
(1)ACD/LogP: 0.731; (2)ACD/LogD (pH 5.5): 0.73; (3)ACD/LogD (pH 7.4): 0.73; (4)ACD/BCF (pH 5.5): 2.12; (5)ACD/BCF (pH 7.4): 2.12; (6)ACD/KOC (pH 5.5): 59.53; (7)ACD/KOC (pH 7.4): 59.53; (8)#H bond acceptors:2; (9)#Freely Rotating Bonds: 1; (10)Index of Refraction: 1.515; (11)Molar Refractivity: 25.305 cm³; (12)Molar Volume: 83.894 cm³; (13)Polarizability: 10.032 10-24cm³; (14)Surface Tension: 36.5740013122559 dyne/cm; (15)Density: 1.145 g/cm³; (16)Flash Point: 58.333 °C; (17)Enthalpy of Vaporization: 39.837 kJ/mol; (18)Boiling Point: 161.799 °C at 760 mmHg; (19)Vapour Pressure: 2.23399996757507 mmHg at 25°C

Preparation of Furfural: 
Many plant materials contain the polysaccharide hemicellulose, a polymer of sugars containing five carbon atoms each. When heated with sulfuric acid, hemicellulose undergoes hydrolysis to yield these sugars, principally xylose. Under the same conditions of heat and acid, xylose and other five carbon sugars undergo dehydration, losing three water molecules to become furfural:
C₅H₁₀O₅ → C₅H₄O₂ + 3 H₂O

Uses of Furfural:
Furfural is used as a solvent in petrochemical refining to extract dienes ( used to make synthetic rubber) from other hydrocarbons . Furfural also can be used either by themselves or in together with phenol, acetone, or urea to make solid resins. It is also used as a chemical intermediate in the production of the solvents furan and tetrahydrofuran.

Safety information of Furfural:
When you are using this chemical, please be cautious about it as the following:(1)In case of contact with eyes, rinse immediately with plenty of water and seek medical advice; (2)Wear suitable protective clothing, gloves and eye/face protection; (3)In case of accident or if you feel unwell, seek medical advice immediately (show label where possible); (4)Keep locked up and out of the reach of children;

You can still convert the following datas into molecular structure:
(1)InChI=1S/C5H4O2/c6-4-5-2-1-3-7-5/h1-4H;
(2)InChIKey=HYBBIBNJHNGZAN-UHFFFAOYSA-N;
(3)Smilesc1(ccco1)C=O;

The toxiciy data of Furfural is as follows: