Spiro Compounds

4 Chapter 4 Figure 4.1 Natural and non‐natural products containing a spirocenter. Figure 4.2 List of ruthenium catalysts used in metathesis. Scheme 4.1 Synthesis of spirocyclic pyrazine. Scheme 4.2 Synthesis of chiral spiro‐connected cyclopentene. Scheme 4.3 Synthesis of spiro[4.5]–decanes. Scheme 4.4 Synthesis of spiro‐lactam. Scheme 4.5 Synthesis of spiro naphthalenone. Scheme 4.6 Synthesis of spiroketal 34. Scheme 4.7 Synthesis of spirocycles.Scheme 4.8 Efficient route to spiroannulated butanolide.Scheme 4.9 Synthesis of a spirocyclic amine 53.Scheme 4.10 Synthesis of spiro carba‐sugar using RCM.Scheme 4.11 Synthesis of novel spiro‐cyclohexene.Scheme 4.12 Synthesis of spiro‐heterocycle.Scheme 4.13 Synthesis of spiro‐center via an Ireland ester CR.Scheme 4.14 Synthesis of spirocyclic compounds through RCM.Scheme 4.15 Synthesis of spiro‐benzosultams.Scheme 4.16 Synthesis of spiro‐azetidine 91.Scheme 4.17 Synthesis of spiroannulated 3‐benzofuranone.Scheme 4.18 Asymmetric synthesis of spiroether.Scheme 4.19 Synthesis of spiro‐Meldrum’s acid derivative.Scheme 4.20 Synthesis of spiro‐lactone.Scheme 4.21 Synthesis of spirocycles starting with active methylene derivati...Scheme 4.22 Synthesis of spiro‐barbituric acid derivative.Scheme 4.23 Synthesis of spiroindolin‐2‐one derivatives.Scheme 4.24 Synthesis of spiro dibenzo[ a , d ]cycloheptene.Scheme 4.25 Synthesis of spiro‐carbohydrate 130.Scheme 4.26 Synthesis of sesquiterpenoid acorenone.Scheme 4.27 Synthesis of (+)‐spirocurcasone.Scheme 4.28 Synthesis of spiroindenes.Scheme 4.29 Synthesis of spiro‐bicyclo[2.2.2]octane 156.Scheme 4.30 Synthesis of oxaspirocyclic compound.Scheme 4.31 Synthesis of spiro‐fused compounds 165.Scheme 4.32 Synthesis of C ‐spiro‐glycoconjugate 168.Scheme 4.33 Synthesis of spiro‐indole derivatives.Scheme 4.34 Synthesis of bis‐spirocycles.Scheme 4.35 Synthesis of bis‐spiro tetralone.Scheme 4.36 Synthesis of spiro‐bicyclic compound 189.Scheme 4.37 Synthesis of spirodione.Scheme 4.38 Synthesis of spiro‐polycyclic compounds.Scheme 4.39 Synthesis of spiro‐fluorene 204.Scheme 4.40 Synthesis of spiro‐truxene 208.Scheme 4.41 Efficient route to (+)‐perhydrohistrionicotoxin.Scheme 4.42 Synthesis of spirocyclic compound 218.Scheme 4.43 Synthesis of spiropiperidine‐3,3‐oxindole.Scheme 4.44 Construction of spiro‐mononitrogen heterocycle.Scheme 4.45 Synthesis of natural product nankakurine.Scheme 4.46 Synthesis of oxa‐aza spiro‐carbohydrate.Scheme 4.47 Synthesis of carbohydrate derivative 243.Scheme 4.48 Synthesis of spiro‐dihydropyran.Scheme 4.49 Synthesis of carbohydrate‐derived spiroacetal 252.Scheme 4.50 Synthesis of spirocyclic 3,6‐dihydro‐2 H ‐pyran 250.Scheme 4.51 Synthesis of spirocyclic oxindole 261.Scheme 4.52 Synthesis of spirocyclic ether 267.Scheme 4.53 Synthesis of spiroannulated carbanucleoside.Scheme 4.54 Synthesis of spirocyclic‐2‐azetidinone.Scheme 4.55 Synthesis of spirocyclic butenolide 280.Scheme 4.56 Synthesis of spiro‐2‐oxazolidinone.Scheme 4.57 Synthetic approach to (+)‐laurencin.Scheme 4.58 Synthesis of spiro oxacycles.Scheme 4.59 Synthesis of ABC ring of nortriterpenoid.Scheme 4.60 Synthesis of spiro‐ C ‐aryl glycoside.Scheme 4.61 Synthesis of cyclic phosphazene.Scheme 4.62 Synthesis of spiroketal 318.Scheme 4.63 Synthesis of anomeric spiroketal 325.Scheme 4.64 Synthesis of spiroketal 331.Scheme 4.65 RRM approach to azepine derivatives.Scheme 4.66 Synthesis of oxa‐spirocycle.Scheme 4.67 RCM of bisallyloxy cyclobutenone to oxa‐spirocycle.Scheme 4.68 Synthesis of spiro‐cage derivative.Scheme 4.69 Synthesis of bis‐oxaspirocycle.Scheme 4.70 Synthesis of oxaspirocycles.Scheme 4.71 Synthesis of spiro indene.Scheme 4.72 Synthesis of spirocycle containing silicon at spioro junction....

5 Chapter 5Figure 5.1 Selected natural products and bioactive molecules containing a sp...Figure 5.2 Asymmetric synthesis of various spirooxindoles via organocatalyti...Scheme 5.1 Double Michael cascade reaction enabled by enamine/iminium sequen...Scheme 5.2 Asymmetric double Michael reactions involving isatylidene malonon...Scheme 5.3 Spirocyclobutaneoxindole synthesis by a stereoselective [2+2] cyc...Scheme 5.4 Three‐component reaction by enamine/iminium/enamine sequential ca...Scheme 5.5 Multicomponent domino reactions by quadruple iminium/enamine/imin...Scheme 5.6 Stereoselective Diels–Alder reaction enabled by trienamine cataly...Scheme 5.7 Asymmetric hetero‐Diels–Alder reaction of α,β‐unsaturated ketones...Scheme 5.8 Asymmetric Michael/Michael/aldol reaction of 3‐unsubsituted oxind...Scheme 5.9 Asymmetric vinylogous cascade reaction of 2,4‐dienals with 3‐hydr...Scheme 5.10 Michael/cyclization sequence of 3‐chlorooxindoles to spirocyclop...Scheme 5.11. Synthesis of spirocyclopentaneoxindoles with 3‐alkyloxindoles 4...Scheme 5.12 Stereoselective Michael/cyclization sequence of 3‐propargyl oxin...Scheme 5.13 Desymmetric intramolecular aldol condensation of 3,3′‐diacetonyl...Scheme 5.14 Chiral phosphine‐catalyzed [3+2] cycloaddition of allene and met...Scheme 5.15 [4+2] Annulation of isatylidene malononitriles and α‐substituted...Scheme 5.16 Asymmetric [3+2] cycloaddition of oxindole‐derived olefins with ...Scheme 5.17 Phosphine‐catalyzed [3+2] annulation of isatin‐derived MBH carbo...Scheme 5.18 Chiral tertiary amines‐catalyzed [3+2] annulation of isatin‐deri...Scheme 5.19 [4+2]‐Cycloaddition of α,β‐unsaturated acyl chlorides by nucleop...Scheme 5.20 Asymmetric [3+2]‐cycloaddition of brominated MBH adducts and ket...Scheme 5.21 Allylic alkylation–cyclization of 3‐hydroxyoxindoles with MBH ca...Scheme 5.22 Chiral NHC‐catalyzed asymmetric annulation involving isatins.Scheme 5.23 Spirooxindole‐δ‐lactones synthesis by NHC‐catalyzed formal [4+2]...Scheme 5.24 Spirooxindole lactams synthesis by NHC‐catalyzed annulation with...Scheme 5.25 Chiral NHC‐catalyzed annulation involving isatin‐derived enals....Scheme 5.26 Stereoselective annulation of isatin‐derived enals with α,β‐unsa...Scheme 5.27 Chiral NHC‐catalyzed asymmetric Michael/aldol/lactonization casc...Scheme 5.28. NHC‐catalyzed annulation with 3‐aminooxindoles or 3‐hydroxyoxin...Scheme 5.29. Tertiary amine‐H bond donor‐catalyzed asymmetric annulation inv...Scheme 5.30. Asymmetric intramolecular [1,5]‐electrocyclization of functiona...Scheme 5.31 Asymmetric annulation of isatin imine by tertiary amine‐H bondin...Scheme 5.32 Asymmetric annulation of methyleneindolinones via double Michael...Scheme 5.33 Asymmetric annulation of methyleneindolinones via Michael‐initia...Scheme 5.34 Asymmetric annulation using isatylidene malononitriles as C2 syn...Scheme 5.35 Asymmetric annulation using isatylidene malononitriles as C3 syn...Scheme 5.36 Asymmetric annulation involving isatin‐derived β,γ‐unsaturated α...Scheme 5.37 Asymmetric annulation involving C3 alkyl ester‐substituted oxind...Scheme 5.38 Asymmetric annulation involving 3‐allyloxindoles.Scheme 5.39 Asymmetric annulation involving 3‐isothiocyanato oxindoles.Scheme 5.40 Asymmetric [4+1] cyclization of 3‐chlorooxindoles with o ‐QMs....Scheme 5.41 Asymmetric cyclopropanation of 3‐unsubstituted oxindoles with α‐...Scheme 5.42 One‐pot Michael/Michael/aldol tandem reaction involving 3‐unsubs...Scheme 5.43 Asymmetric desymmetrization of spiro cyclohexadienone oxindoles....Scheme 5.44 Enantioselective Diels–Alder reaction of methyleneindolinones wi...Scheme 5.45 Asymmetric [3+2] cycloaddition of methyleneindolinone and nitron...Scheme 5.46 Asymmetric MCR of diazooxindoles, nitrosoarenes, and nitroalkene...Scheme 5.47 Enantioselective cyclization reaction of isatin and 2‐aminobenza...Scheme 5.48 Asymmetric three‐component 1,3‐dipolar cycloaddition by phosphor...Scheme 5.49 Asymmetric three‐component 1,3‐dipolar cycloaddition.Scheme 5.50 Asymmetric three‐component 1,3‐dipolar cycloaddition.Scheme 5.51 Chiral phosphoric acid‐catalyzed cycloaddition with methyleneind...Scheme 5.52 [3+2] Cycloaddition of isatin‐derived 3‐indolylmethanols and 2‐v...Scheme 5.53 Chiral phosphoric acid‐catalyzed kinetic resolution of racemic s...Scheme 5.54 Asymmetric double Michael cascade reaction of 3‐alkenyloxindoles...Scheme 5.55 Enantioselective 1,3‐dipolar cycloaddition of 3‐alkenyloxindoles...Scheme 5.56 Intramolecular C ‐acylation of 3‐substituted oxindoles 320by PTC...Scheme 5.57 Enantioselective direct intramolecular C(sp 2)–H/C(sp 3)–H oxidati...Scheme 5.58 Chiral organoiodine‐catalyzed oxidative dearomatization of pheno...