The 2,3,6,7-Tetrahydro-8-hydroxy-1H,5H-benzo[ij]quinolizine-9-carboxaldehyde, with the CAS registry number 63149-33-7 and EINECS registry number 263-966-4, has the systematic name of 8-hydroxy-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinoline-9-carbaldehyde. And the molecular formula of the chemical is C₁₃H₁₅NO₂.

The characteristics of this chemical are as followings: (1)ACD/LogP: 2.68; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 2.67; (4)ACD/LogD (pH 7.4): 2.67; (5)ACD/BCF (pH 5.5): 63.5; (6)ACD/BCF (pH 7.4): 62.93; (7)ACD/KOC (pH 5.5): 678.89; (8)ACD/KOC (pH 7.4): 672.83; (9)#H bond acceptors: 3; (10)#H bond donors: 1; (11)#Freely Rotating Bonds: 2; (12)Polar Surface Area: 29.54 Å²; (13)Index of Refraction: 1.648; (14)Molar Refractivity: 60.81 cm³; (15)Molar Volume: 167 cm³; (16)Polarizability: 24.1×10^-24cm³; (17)Surface Tension: 62.8 dyne/cm; (18)Density: 1.3 g/cm³; (19)Flash Point: 206.2 °C; (20)Enthalpy of Vaporization: 69.67 kJ/mol; (21)Boiling Point: 417.3 °C at 760 mmHg; (22)Vapour Pressure: 1.47E-07 mmHg at 25°C. 

Preparation of 2,3,6,7-Tetrahydro-8-hydroxy-1H,5H-benzo[ij]quinolizine-9-carboxaldehyde: This chemical can be prepared by N,N-dimethyl-formamide and 2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-8-ol. The reaction will need reagent POCl₃, and the menstruum dimethylformamide. The reaction time is 1 hour with the room temperature, and the yield is about 16%. 

Uses of 2,3,6,7-Tetrahydro-8-hydroxy-1H,5H-benzo[ij]quinolizine-9-carboxaldehyde: It can react with nitroacetic acid ethyl ester to produce 10-nitro-2,3,6,7-tetrahydro-11-oxo-1H,5H,11H-benzo[b]pyrano[6,7,8-i,j]quinolizine. This reaction will need reagent acetic acid and piperidine, and the menstruum butan-1-ol. The reaction time is 43 hours with heating, and the yield is about 84%.

You should be cautious while dealing with this chemical. It irritates to eyes, respiratory system and skin. Therefore, you had better take the following instructions: Wear suitable protective clothing, and if in case of contacting with eyes, rinse immediately with plenty of water and seek medical advice.

Addtionally, the following datas could be converted into the molecular structure:
(1)SMILES: O=Cc1cc3c2c(c1O)CCCN2CCC3
(2)InChI: O=Cc1cc3c2c(c1O)CCCN2CCC3
(3)InChIKey: NRZXBDYODHLZBF-UHFFFAOYAX