ketene

Reported in EPA TSCA Inventory. EPA Genetic Toxicology Program.

OSHA PEL: TWA 0.5 ppm; STEL 1.5 ppm
ACGIH TLV: TWA 0.5 ppm; STEL 1.5 ppm
DFG MAK: 0.5 ppm (0.87 mg/m³)

The IUPAC name of this chemical is ethenone. With the CAS registry number 463-51-4 and EINECS registry number 207-336-9, it is also named as ketene. In addition, it is an organic compound which was first studied as a class by Hermann Staudinger. It mainly used in the manufacture of acetic anhydride and acetylation reagent. What's more, it should be stored in sealed container, and put in a cool and dry place.

Physical properties about this chemical are: (1)ACD/LogP: 0.11; (2)ACD/LogD (pH 5.5): 0.11; (3)ACD/LogD (pH 7.4): 0.11; (4)ACD/BCF (pH 5.5): 1; (5)ACD/BCF (pH 7.4): 1; (6)ACD/KOC (pH 5.5): 27.4; (7)ACD/KOC (pH 7.4): 27.4; (8)#H bond acceptors: 1; (9)Polar Surface Area: 17.07 Å²; (10)Index of Refraction: 1.303; (11)Molar Refractivity: 11.15 cm³; (12)Molar Volume: 58.9 cm³; (13)Polarizability: 4.42 ×10^-24cm³; (14)Surface Tension: 3.5 dyne/cm; (15)Density: 0.712 g/cm³; (16)Enthalpy of Vaporization: 20.2 kJ/mol; (17)Vapour Pressure: 12600 mmHg at 25°C.

Preparation of ketene: it can be formed by pyrolysis (thermal cracking) of acetone: CH₃−CO−CH₃ + ΔT → CH₂=C=O + CH₄. In addition, it can also be formed from α-diazoketones by Wolff rearrangement.

Uses of ketene: it can react with hexan-1-ol to get 1-acetoxy-hexane. This reaction will need reagent MgO. The reaction time is 1 hour with ambient temperature. The yield is about 86%.

When you are using this chemical, please be cautious about it as the following:
This chemical irritats eyes, skin, nose, throat and respiratory system. When you are using it, wear suitable protective clothing, gloves and eye/face protection. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.

You can still convert the following datas into molecular structure:
(1)SMILES: O=C=C
(2)Std. InChI: InChI=1S/C2H2O/c1-2-3/h1H2
(3)Std. InChIKey: CCGKOQOJPYTBIH-UHFFFAOYSA-N

The toxicity data is as follows:

Organism	Test Type	Route	Reported Dose (Normalized Dose)	Effect	Source
cat	LCLo	inhalation	750ppm/10M (750ppm)	LUNGS, THORAX, OR RESPIRATION: ACUTE PULMONARY EDEMA LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES GASTROINTESTINAL: CHANGES IN STRUCTURE OR FUNCTION OF SALIVARY GLANDS	Journal of Industrial Hygiene and Toxicology. Vol. 31, Pg. 209, 1949.
guinea pig	LCLo	inhalation	53ppm/2H (53ppm)	LUNGS, THORAX, OR RESPIRATION: ACUTE PULMONARY EDEMA LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES	Journal of Industrial Hygiene and Toxicology. Vol. 31, Pg. 209, 1949.
monkey	LCLo	inhalation	200ppm/10M (200ppm)	SENSE ORGANS AND SPECIAL SENSES: PTOSIS: EYE LUNGS, THORAX, OR RESPIRATION: ACUTE PULMONARY EDEMA LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES	Journal of Industrial Hygiene and Toxicology. Vol. 31, Pg. 209, 1949.
mouse	LCLo	inhalation	23ppm/30M (23ppm)	BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD LUNGS, THORAX, OR RESPIRATION: DYSPNEA	Journal of Industrial Hygiene and Toxicology. Vol. 31, Pg. 209, 1949.
rabbit	LCLo	inhalation	53ppm/2H (53ppm)	LUNGS, THORAX, OR RESPIRATION: ACUTE PULMONARY EDEMA LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES	Journal of Industrial Hygiene and Toxicology. Vol. 31, Pg. 209, 1949.