ライフサイエンスコーパス: pinacol

1 he ferroceneboronate derivative of the diol, pinacol.

2 e the aerobic oxidative C-C bond cleavage of pinacol.

3 Treatment of the boronate with pinacol/acetic acid afforded the corresponding diol whic

4 xamples of primary and secondary amines with pinacol allenylboronate is presented.

5 Transformation to the corresponding pinacol and neopentyl glycol boronates and stereoselecti

6 (on the basis of the transesterification of pinacol aryl boronates (aryl-Bpins) with methyl boronic

7 end-capped with a triallylsilyl group and a pinacol arylboronate group was readily derived from diio

8 ed through the development of a novel hetero-pinacol-based macrocyclization cascade sequence.

9 By changing the reducing agent from pinacol borane (HBpin) to phenyl silane (H(3)SiPh), we c

10 Reaction of (tBuPOCOP)IrH2 with pinacol borane gave initially complex 2, which is assign

11 of the (tBuPOCOP)Ir core with a sigma-bound pinacol borane ligand in an approximately square planar

12 e hexafluorobenzene, triphenylphosphine, and pinacol borane, catalytically dehydrogenate cyclohexene,

13 nexpensive and atom-economical boron source, pinacol borane, has been developed.

14 (18)F]FDOPA by Cu-mediated fluorination of a pinacol boronate (BPin) precursor.

15 adily available 3-carbomethoxy-2-nitrophenyl pinacol boronate afforded the hindered highly functional

16 alyzed olefin cross-metathesis of 1-propenyl pinacol boronate and various alkenes, including function

17 ifferent scenario, considering tricoordinate pinacol boronate as a boryl migrating group.

18 droxyl functional group positioned beta to a pinacol boronate can serve to direct palladium-catalyzed

19 It is noted that the one-pot pinacol boronate cross-coupling reaction generally provi

20 Chan-Lam coupling between a halogenated aryl pinacol boronate ester and an aryl methanesulfonamide.

21 A copper-promoted coupling of vinyl pinacol boronate esters and alcohols for the synthesis o

22 e protected to form synthetically ubiquitous pinacol boronate esters or used in situ in Suzuki-Miyaur

23 0 microM] were prepared via routes involving pinacol boronate esters, which were deprotected via a tw

24 ved in situ and the products isolated as the pinacol boronate esters.

25 y of functional groups, to the corresponding pinacol boronate esters.

26 rifluoroborate, neopentylglycolboronate, and pinacol boronate in nickel-catalyzed Suzuki-Miyaura cros

27 tiomeric excess with prior conversion of the pinacol boronate to the corresponding trifluoroborate sa

28 ctive Suzuki coupling of sterically hindered pinacol boronate with aryl iodide in the presence of mul

29 to Suzuki and Buchwald-Hartwig couplings, as pinacol boronates and anilines are tolerated and, owing

30 The direct amination of alkyl and aryl pinacol boronates is accomplished with lithiated methoxy

31 Functionalized vinyl pinacol boronates suitable for Suzuki cross-coupling rea

32 transformation of rapidly decomposing enynyl pinacol boronates to more stable silica-based column chr

33 dioxaborole COFs (through the metathesis of pinacol boronates with MBA-protected catechols).

34 The reaction of bicyclo[1.1.0]butyl pinacol boronic ester (BCB-Bpin) with nucleophiles has b

35 We found that addition of nBuLi to the pinacol boronic ester followed by trapping of the alkoxi

36 The synthetically versatile pinacol boronic ester group (Bpin) is generally thought

37 lalkanes that also incorporate an additional pinacol boronic ester which can be easily transformed to

38 A simple workup allows isolation of the pinacol boronic ester.

39 plexed lithiated carbamates with (Z)-alkenyl pinacol boronic esters and (E)-alkenyl neopentyl boronic

40 Boron "ate" complexes derived from pinacol boronic esters and tert-butyl lithium undergo st

41 Allylic pinacol boronic esters are stable toward 1,3-borotropic

42 rearrangements for the synthesis of a-chloro pinacol boronic esters from readily available boronic es

43 -Miyaura cross-coupling of the tosylates and pinacol boronic esters in the presence of a Pd(OAc)2/RuP

44 ly available, alpha-substituted allyl/crotyl pinacol boronic esters often give low E/Z selectivity (w

45 thodology for the protodeboronation of alkyl pinacol boronic esters that involves the formation of a

46 alpha,alpha-Disubstituted allylic pinacol boronic esters undergo highly selective allylbor

47 ation of acetophenone oxime ethers with aryl pinacol boronic esters, leading to the synthesis of biar

48 However, using pinacol boronic esters, the boron moiety migrates to the

49 th unsubstituted and alpha-substituted vinyl pinacol boronic esters.

50 and the previously unreported beta-methallyl pinacol boronic esters.

51 a-Vinyl boronates, in particular pinacol (Bpin) derivatives, are excellent hydrogen atom

52 However, aryl boronic acid pinacol (BPin) ester reagents can be difficult coupling

53 stensibly equivalently reactive boronic acid pinacol (BPin) esters by kinetic discrimination during t

54 yl complex also underwent diastereoselective pinacol coupling (22:1 dr).

55 d through a strategy combining a challenging pinacol coupling and bicycle-forming etherification with

56 mportant C-C bond-forming reactions, such as pinacol coupling and McMurry chemistry, the mechanism of

57 lactonization; SmI2-mediated intramolecular pinacol coupling between ketone and lactone subunits to

58 A cross-selective aza-pinacol coupling of aldehydes and imines has been develo

59 The formation of carbon-carbon bonds by pinacol coupling of aldehydes and ketones requires a lar

60 The chlorosulfonylation of alkenes and the pinacol coupling of aldehydes and ketones were conducted

61 arbonyl complexes were also prepared, though pinacol coupling of these substrates proceeded in, at be

62 pported acids enhance the selectivity of the pinacol coupling reaction compared with homogeneous acid

63 The first continuous flow pinacol coupling reaction of carbonyl compounds was succ

64 Vanadium-based pinacol coupling reactions were explored for closure of

65 Efficient pinacol coupling was developed in sole water, using a re

66 In these latter cases the pinacol coupling was diastereorandom.

67 It was found that the pinacol coupling, promoted by VCl(3) x (THF)(3)/Zn, proc

68 etones and aldehydes to give the products of pinacol coupling.

69 y and diastereoselectivity of intramolecular pinacol couplings on such substrates.

70 ed herein represent the first intramolecular pinacol couplings performed on the periphery of an iron(

71 All attempts at a pinacol cyclization or an intramolecular 6-exo-tet epoxi

72 e ketone alkylation and a diastereoselective pinacol cyclization.

73 uents are formed stereospecifically by Prins-pinacol cyclizations of unsaturated alpha-dithianyl acet

74 Several pinacol derivatives of podophyllotoxins bearing differen

75 on, and attempted alpha-deprotonation of the pinacol derived alkyl phosphonates resulted in ring clea

76 nts with the production of (18)F arenes from pinacol-derived aryl boronic esters (arylBPin) upon trea

77 vinyl appendage and a Takai olefination with pinacol dichloromethylboronate.

78 um metal and either allylboronic acid or the pinacol ester (allylBpin) as donors.

79 s (CAL-3-Ir) can produce methyl boronic acid pinacol ester (CH(3) Bpin) in 29 % yield in 9 h with a t

80 antioselective addition of allylboronic acid pinacol ester [allylB(pin)] to alpha,beta,gamma,delta-un

81 on of starting ketone with allylboronic acid pinacol ester and methanolic ammonia, and cross metathes

82 oss-coupling reaction with allylboronic acid pinacol ester and titanium assisted cross-metathesis (CM

83 utility of a 2-aminopyridine-5-boronic acid pinacol ester as a robust and versatile building block f

84 ar prenylation at C4 of l-tryptophan boronic pinacol ester derivate, the latter obtained by a Lewis a

85 ross-coupling reactions of allylboronic acid pinacol ester derivatives with aryl and heteroaryl halid

86 m (S)-nicotine containing a C-4 boronic acid pinacol ester group.

87 is based on the use of an alkylboronic acid pinacol ester initiator, which allows for controlled, un

88 Commercially available allenylboronic acid pinacol ester is used.

89 sp-Csp cross-coupling of alkynyl bromide and pinacol ester of alkynyl boronic acid catalyzed by CuFe2

90 ediated (123)I iododeboronation of a boronic pinacol ester precursor afforded [(123)I]CC1.

91 ino-2,2':6',2''-terpyridine-6''-boronic acid pinacol ester) to promote directed Lewis acid/base inter

92 combination of hexyl 2-bromo-5-(boronic acid pinacol ester)furan-3-carboxylate with tris(dibenzyliden

93 actions with unsubstituted allylboronic acid pinacol ester, additions to ketones with a mono- or a di

94 e Diels-Alder reactions of vinylboronic acid pinacol ester, allenylboronic acid pinacol ester, methyl

95 antioselective addition of allylboronic acid pinacol ester, allylB(pin), is described.

96 onic acid pinacol ester, allenylboronic acid pinacol ester, methyl acrylate, and methyl 2,3-butadieno

97 a Z- or an E-gamma-substituted boronic acid pinacol ester.

98 boronic ester (1,4-benzenediboronic acid bis(pinacol)ester).

99 Alkylboronic pinacol esters (APEs) are highly versatile reagents in o

100 oles has been explored with arylboronic acid pinacol esters (arylBpin).

101 nctionalization of bridgehead (C(3))-boronic pinacol esters (Bpin), leaving the C(2)-Bpin intact and

102 Alkyl boronic pinacol esters (Bpins), though stable and widely accessi

103 ic acids can also be applied to boronic acid pinacol esters and potassium organotrifluoroborates usin

104 Employing arylboronic acid pinacol esters and Rh/(R)-Xyl-BINAP, the reaction tolera

105 (46-99%) from a variety of arylboronic acid pinacol esters and substituted o-allylbenzamides.

106 Aryl boronic acids or pinacol esters containing EDG were converted in good yie

107 ity afforded by the pendant bridgehead boron pinacol esters generated during the cyclization reaction

108 cted diarylmethylamines and arylboronic acid pinacol esters has been achieved utilizing chiral mono-N

109 ted radiobromination of (hetero)aryl boronic pinacol esters is described.

110 ect C-H activation with arylboronic acids or pinacol esters is presented.

111 tosylate substrates using boronic acids and pinacol esters is reported.

112 ercial or readily accessed aryl boronic acid pinacol esters with alkyl lithium reagents provides boro

113 veral common boronic acid derivatives (e.g., pinacol esters).

114 with various lithium nbutyl arylboronic acid pinacol esters, alkyne and heteroarene.

115 ing using synthetically modular alkylboronic pinacol esters.

116 acids as well as 2-formylphenylboronic acid pinacol esters.

117 wo steps from the corresponding aryl boronic pinacol esters.

118 n of o-allylbenzamides with arylboronic acid pinacol esters.

119 omologation of aryl and alkenyl boronic acid pinacol esters.

120 e imine carbon and one of the oxygens of the pinacol group was observed in the six-membered ring tran

121 The final step was thwarted by a pinacol-like rearrangement that delivered the unnatural

122 amides C (11) and D (12) through an apparent pinacol-like rearrangement.

123 Under pinacol-pinacolone conditions, vic-dihydroxy chlorins co

124 neral substituent migratory aptitudes in the pinacol-pinacolone rearrangement based on simple electro

125 own one-pot epoxidation/epoxide ring-opening/pinacol-pinacolone rearrangement of octaethylporphyrin (

126 f porphyrins with osmium tetraoxide, and the pinacol-pinacolone rearrangement of the resulting diols,

127 s among ketobacteriochlorins obtained in the pinacol-pinacolone rearrangements of vic-dihydroxybacter

128 rangement that is terminated by a thio-Prins-pinacol reaction is also identified.

129 Prins-pinacol reactions of these precursors promoted by SnCl4

130 Two new tandem cationic olefin cyclization-pinacol reactions that provide cyclopentane-fused cycloa

131 This occurs through a BvnE-controlled semi-pinacol rearrangement and a subsequent spontaneous intra

132 of BF(3).Et(2)O with 10a led to a novel aza-pinacol rearrangement and allylation at the alpha-carbon

133 ane featuring the catalytic enantioselective pinacol rearrangement as a key strategic step is also do

134 this synthesis also employs an oxidation and pinacol rearrangement for the formation of the oxindole

135 The development of enantioselective pinacol rearrangement is extremely challenging due to th

136 The pivotal pinacol rearrangement is further examined through DFT ca

137 lyl phosphoramide-catalyzed enantioselective pinacol rearrangement of 1,2-tertiary diols and mechanis

138 A recently developed aza-Prins-pinacol rearrangement was employed for the construction

139 The pinacol rearrangement, benzannulation, and oxy-Cope rear

140 tion, the acid-promoted (or catalyzed) Prins-pinacol rearrangement, with particular emphasis on its i

141 diphenylacetaldehyde (9) was generated via a Pinacol rearrangement.

142 rearrangement, and Lewis acid mediated semi-Pinacol rearrangement.

143 A variety of competitive pinacol rearrangements and cyclization reactions were ov

144 lar routes described include EtMgBr-promoted pinacol ring expansions of hydroxy mesylates 23 and 34,

145 n the making, is loosely modeled after a key pinacol shift in the proposed biosynthesis.

146 Along with pinacols, some C-7 alkylidene and C-7 alkyl derivatives

147 he extraneous carbon introduced in the Prins-pinacol step; chemo- and stereoselective hydroxyl-direct

148 Key steps are as follows: (a) a pinacol-terminated 1,6-enyne cyclization reaction to for

149 nal illustrations of the uncommon utility of pinacol-terminated cationic cyclizations for the stereoc

150 During this study, a number of pinacol-terminated cationic cyclizations were examined t

151 on of the triple bond, carbocyclization, and pinacol-type 1,2-shift.

152 performance for hydrogenative N-N coupling, pinacol-type coupling and dehalogenative C-C coupling, a

153 the A-ring with a subsequent SmI(2)-mediated pinacol-type coupling to reclose the A-ring following re

154 nclude a palladium-catalyzed decarboxylative pinacol-type rearrangement of an allylic carbonate to in

155 drofuran) subunit by a Lewis acid-catalyzed, pinacol-type rearrangement of an epoxy silyl ether.

156 Facile pinacol-type rearrangement of the alpha-hydroxycycloprop

157 A Bronsted acid-catalyzed pinacol-type rearrangement pathway is reported here to s

158 ately, we implemented a novel cyclic sulfite pinacol-type rearrangement to generate the strained ring

159 ynthesis of 3-aryl-1-propenyl boronates from pinacol vinyl boronic ester and allyl-substituted aromat