5869-13-6Relevant academic research and scientific papers
Stereoselectivity and Stereospecificity in Reductions of Some Hexahydro-3-oxophenanthrene Derivatives with Various Reducing Agents
Chatterjee, S. K.,Bhattacharya, S.,Raychaudhuri, S.R.,Chatterjee, A.
, p. 1191 - 1199 (2007/10/02)
Catalytic and chemical reduction of hexahydro-3-oxophenanthrene derivatives (1a,b) and (1d,e) are reported.Catalytic hydrogenation (Pd/C,10percent) of 1a and 1b in acidic medium affords predominantly the trans-fused hydrocarbons (2a) and (2c) respectively, whereas similar hydrogenation of 1a in pyridine solution gives the cis-fused ketone (3b) as the major product.Birch reduction of 1a and 1b affords in each case a 65:35 mixture of the corresponding saturated cis- and trans-fused ketones.Reduction of 1a and 1b with Ni-Al alloy and alkali followed by oxidation furnish selectively the trans-fused ketones (3a) and (3c).Lithium aluminium hydride reduction of 1a,b and 1d,e followed by oxidation provided exclusively the cis-fused ketones (3b),(3d),(3f), and (3h) respectively.The stereospecificity observed in LAH reduction, and the lower yields of the reduction products in the case of 1b and 1e, have been rationalised.
Stereospecific cis-Reduction of Hexahydro-3-oxophenanthrene Derivatives. Total Synthesis of a New Class of Ring-c Aromatic Steroid
Chatterjee, Amareshwar,Chaudhuri, Swadesh R. Ray,Chatterjee, Swapan K.
, p. 24 - 25 (2007/10/02)
Catalytic hydrogenation (Pd/C, 10percent) of the hexahydro-3-oxophenanthrene (2a) in acidic medium gave the trans-fused octahydrophenanthrene ring system (5b) predominantly, whereas reduction of (2a-c) with LiAlH4 followed by oxidation gave exclusively the cis-fused systems (4a), (4c), and (4e), respectively; the products (4a) and (5b) have been elaborated to the 10βH and 10αH isomers, respectively, of 5,12-dimethyl-5β-gonane-8,11,13-triene-17-one.
