Cyclohexane selective ring opening

Perhaps the greatest utility of (36-39) (and many of their precursors, such as 41, 42 and 48) is as starting points for the synthesis of highly functionalized cyclohexanes. For example, (38) has been converted in five steps (overall yield 70-75%) to streptamine (57) the key step is selective ring-opening with hydrazine to give intermediate (56) (75AG(E)630). 

The first reported synthesis of a member of this class, that of erythronolide B, was completed by Corey and is depicted in Scheme 2.14. The retrosynthetic strategy involved the use of two segments, C-10 to C-13 and C-1 to C-9, the former arising from selective ring opening of an epoxide and the latter from a series of manipulations on a rigid cyclohexane derivative. 

Selective transformations Selective styrene ring opening [103] One-pot domino process for regioselective synthesis of a-carbonyl furans [104] Tandem process for synthesis of quinoxalines [105] Atmospheric oxidation of toluene [106] Cyclohexane oxidation [107] Synthesis of imines from alcohols [108] Synthesis of 2-aminodiphenylamine [109] 9H-Fluorene oxidation [110] Dehydrogenation of ethane in the presence of C02 [111] Decomposition of methane [112] Carbon monoxide oxidation [113]... 

Ring-opening of alkyl-substituted cyclohexanes is slower and much less selective selectivity was only about 5% with platinum, although Ir/A Os gave 87% C7 alkanes. Lower values were found with n-butylcyclohexane. ... 

Figure 7.32. K-Receptor selective agonists with alternative ring systems and open chain analogs of the 1,2-diainine substituted cyclohexane ring.

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