of 23
Supporting Information for:
Proton-Hydride Tautomerism in Hydrogen Evolution Catalysis
Luis M. Aguirre Quintana,
1
Samantha I. Johnson,
1
Sydney Corona,
1
Walter Villatoro,
1
William A. Goddard III,
1
Michael K. Takase,
1
David G. VanderVelde,
1
Jay R. Winkler,
1
* Harry B. Gray,
1
* and James D. Blakemore
1,2
*
1
Beckman Institute, and Division of
Chemistry and Chemical Engin
eering, California Institute of
Technology, 1200 E. California Blvd.
, Pasadena, California 9112
5, USA
2
Department of Chemistry, Unive
rsity of Kansas, Malott Hall, 125
1 Wescoe Hall Drive,
Lawrence, Kansas 66044, USA
*Correspondence to: blakemore@
ku.edu (JDB); hbgray@caltech.edu
(HBG);
winklerj@caltech.edu (JRW)
Figure S1.
1
H NMR spectrum of
3
with excess [Et
3
NH]
+
Br
.
Figure S2.
1
H NMR spectrum of
3
with excess [Et
3
NH]
+
Br
. * indicates a small impurity of free
2,2 ́-bipyridyl. # is adventitious hexane from glovebox atmosphe
re.
Figure S3.
Alkyl region of the
1
H NMR spectrum of
3
with excess [Et
3
NH]
+
Br
. This region
highlights the peaks
corresponding to Rh-bound Cp*H.
Figure S4.
13
C NMR spectrum of
3
with excess [Et
3
NH]
+
Br
. * is MeCN solvent residual. # is
[Et
3
NH]
+
.
Figure S5.
13
C NMR spectrum of
3
with excess [Et
3
NH]
+
Br
.
Figure S6.
Comparison of
1
H NMR spectra of
4
before and after addition of ~2 eq. of
[DMF·H]
+
OTf
. $ is
1,3,5
-(OMe)
3
C
6
H
3
internal standard. # is [Et
3
NH]
+
/Et
3
N.
D
is
dimethyformamide.
*
is
4
.
*
is dihydrogen.
*
is [Cp*Rh
III
].
Figure S7.
Comparison of
1
H NMR spectra in the alkyl region of
4
before and after addition of
~2 eq. of [DMF·H]
+
OTf
. # is [Et
3
NH]
+
/Et
3
N.
D
is dimethyformamide.
*
is
4
.
*
is dihydrogen.
*
is [Cp*Rh
III
].
Figure S8
. Gas chromatography data for determination of evolved H
2
evolution upon
progressive additions of 1 eq. of [Et
3
NH]
+
OTf
, 1 eq. of [DMF·H]
+
OTf
, and a further 1 eq. of
[DMF·H]
+
OTf
to
1
.
Figure S9.
Gas chromatography data for determination of evolved H
2
evolution upon
progressive additions of 1 eq. of [Et
3
NH]
+
OTf
, 1 eq. of [DMF·H]
+
OTf
, and a further 1 eq. of
[DMF·H]
+
OTf
to
2
.
Figure S10.
Absorption spectra of
1
and
3
in MeCN.
Figure S11.
Absorption spectra of
2
, (Cp*H)Rh(phen)Br, and [Cp*Rh(phen)]
+
. [Cp*Rh(phen)]
+
was generated by treatment of (
Cp*H)Rh(phen)Br with [DMF·H]
+
OTf
.
Figure S12.
Absorption spectra of (Cp*H)R
h(bpy)Br and (Cp*H)Rh(phen)Br.
X-ray Crystal Structure Data
Table S1.
Crystal data and structure refinement for
3
.
Chemical Data
Chemical formula
C
20
H
24
Br N
2
Rh C
2
H
3
N
Formula weight
516.28
Crystallization solvent
Acetonitrile
Crystal habit
Block
Crystal size
0.35 x 0.15 x 0.15 mm
3
Crystal color
Orange
Data Collection
Type of diffractometer
Bruker D8
VENTURE Kappa Duo PHOTON 100
Wavelength
0.71073
Data collection temperature
100(2) K
Crystal system
Orthorhombic
Space group
Pnma
Cell dimensions
a = 22.003(2) Å α = 90°
b = 12.3185(10) Å β = 90°
c = 7.8446(7) Å γ = 90°
Cell volume
2126.3(3) Å
3
Z
4
Density (calculated)
1.613 mg/cm
3
F(000)
1040
q range for data collection
2.757 to 36.302°
Index ranges
–36
§
h
§
36 ; –20
§
k
§
20 ; –13
§
l
§
12
Data collection scan type
φ and ω scans
Reflections collected
28033
Absorption coefficient
2.694
Min. and max. transmission
0.6266 and 0.7471
Refinement
Structure solution program
SHELXS-2013/1 (Sheldrick, 2012)
Structure refinement program
SHELXL-2014/7 (Sheldrick, 2014)
Refinement method
Full matrix least-squares on F
2
Data/restraints/parameters
5308 / 1 / 139
Goodness of fit
1.009
Final R indices
[I > 2σ (I), 3970]
R1 = 0.0316, wR2 = 0.0545
R indices (all data)
R1 = 0.0559, wR2 = 0.0603
Weighting scheme
Calculated
w = 1 / [σ
2
F
o
2
+(0.0222P)
2
+ 1.0579P]
P = (F
o
2
+ 2F
c
2
) / 3
Max shift/error
0.002
Average shift/error
0.000
Largest diff. peak and hole
0.660 and –0.754 e
3
Table S2.
Selected bond lengths (Å) for
3
.
Rh(1)-C(3)#1 2.1122(15)
Rh(1)-C(3) 2.1122(15)
Rh(1)-N(1)#1 2.1165(12)
Rh(1)-N(1) 2.1165(12)
Rh(1)-C(2)#1 2.1328(14)
Rh(1)-C(2) 2.1328(14)
Rh(1)-Br(1) 2.6512(3)
N(1)-C(11) 1.3415(19)
N(1)-C(15) 1.3574(18)
C(1)-C(2)
1.523(2)
C(1)-C(2)#1 1.523(2)
C(1)-C(6)
1.537(3)
C(1)-H(1)
0.982(16)
C(2)-C(3)
1.442(2)
C(2)-C(7)
1.501(2)
C(3)-C(3)#1 1.442(3)
C(3)-C(8)
1.497(2)
C(6)-H(6A) 0.98
C(6)-H(6B) 0.98
C(6)-H(6C) 0.98
C(7)-H(7A) 0.98
C(7)-H(7B) 0.98
C(7)-H(7C) 0.98
C(8)-H(8A) 0.98
C(8)-H(8B) 0.98
C(8)-H(8C) 0.98
C(11)-C(12) 1.386(2)
C(11)-H(11) 0.95
C(12)-C(13) 1.392(2)
C(12)-H(12) 0.95
C(13)-C(14) 1.383(2)
C(13)-H(13) 0.95
C(14)-C(15) 1.395(2)
C(14)-H(14) 0.95
C(15)-C(15)#1 1.475(3)
N(1S)-C(1S) 1.136(3)
C(1S)-C(2S) 1.464(4)
C(2S)-H(2S1) 0.98
C(2S)-H(2S2) 0.98
C(2S)-H(2S3) 0.98
Table S3.
Selected bond angles (°) for
3
.
C(3)#1-Rh(1)-C(3)
39.91(8)
H(7A)-C(7)-H(7C)
109.5
C(3)#1-Rh(1)-N(1)#1 107.27(5)
H(7B)-C(7)-H(7C)
109.5
C(3)-Rh(1)-N(1)#1
136.23(5)
C(3)-C(8)-H(8A)
109.5
C(3)#1-Rh(1)-N(1)
136.23(5)
C(3)-C(8)-H(8B)
109.5
C(3)-Rh(1)-N(1)
107.27(5)
H(8A)-C(8)-H(8B)
109.5
N(1)#1-Rh(1)-N(1)
77.09(6)
C(3)-C(8)-H(8C)
109.5
C(3)#1-Rh(1)-C(2)#1 39.72(
6)
H(8A)-C(8)-H(8C)
109.5
C(3)-Rh(1)-C(2)#1
66.03(6)
H(8B)-C(8)-H(8C)
109.5
N(1)#1-Rh(1)-C(2)#1 109.25(5)
N(1)-C(11)-C(12)
123.02(14)
N(1)-Rh(1)-C(2)#1
172.90(5)
N(1)-C(11)-H(11)
118.5
C(3)#1-Rh(1)-C(2)
66.03(6)
C(12)-C(11)-H(11)
118.5
C(3)-Rh(1)-C(2)
39.72(6)
C(11)-C(12)-C(13)
118.69(14)
N(1)#1-Rh(1)-C(2)
172.90(5)
C(11)-C(12)-H(12)
120.7
N(1)-Rh(1)-C(2)
109.25(5)
C(13)-C(12)-H(12)
120.7
C(2)#1-Rh(1)-C(2)
64.24(8)
C
(14)-C(13)-C(12)
118.84(14)
C(3)#1-Rh(1)-Br(1)
138.05(4)
C(14)-C(13)-H(13)
120.6
C(3)-Rh(1)-Br(1)
138.05(4)
C(12)-C(13)-H(13)
120.6
N(1)#1-Rh(1)-Br(1)
85.18(3)
C(13)-C(14)-C(15)
119.50(14)
N(1)-Rh(1)-Br(1)
85.18(3)
C(13)-C(14)-H(14)
120.3
C(2)#1-Rh(1)-Br(1)
98.36(4)
C(15)-C(14)-H(14)
120.3
C(2)-Rh(1)-Br(1)
98.36(4)
N(1)-C(15)-C(14)
121.57(13)
C(11)-N(1)-C(15)
118.37(12)
N(
1)-C(15)-C(15)#1 115.36(8)
C(11)-N(1)-Rh(1)
125.36(10)
C(
14)-C(15)-C(15)#1 123.05(9)
C(15)-N(1)-Rh(1)
115.59(9)
N(1
S)-C(1S)-C(2S)
179.3(3)
C(2)-C(1)-C(2)#1
96.24(16)
C(1S)-C(2S)-H(2S1) 109.5
C(2)-C(1)-C(6)
115.50(12)
C(1S)-C(2S)-H(2S2) 109.5
C(2)#1-C(1)-C(6)
115.50(12)
H(2S1)-C(2S)-H(2S2) 109.5
C(2)-C(1)-H(1)
108.4(10)
C(1S)-C(2S)-H(2S3) 109.5
C(2)#1-C(1)-H(1)
108.4(10)
H(2S1)-C(2S)-H(2S3) 109.5
C(6)-C(1)-H(1)
111.6(16)
H(2S2)-C(2S)-H(2S3) 109.5
C(3)-C(2)-C(7)
125.65(14)
C(3)-C(2)-C(1)
108.78(13)
C(7)-C(2)-C(1)
120.67(13)
C(3)-C(2)-Rh(1)
69.37(8)
C(7)-C(2)-Rh(1)
126.60(11)
C(1)-C(2)-Rh(1)
91.19(10)
C(3)#1-C(3)-C(2)
106.65(9)
C(3)#1-C(3)-C(8)
125.66(9)
C(2)-C(3)-C(8)
127.68(14)
C(3)#1-C(3)-Rh(1)
70.04(4)
C(2)-C(3)-Rh(1)
70.91(8)
C(8)-C(3)-Rh(1)
124.98(10)
C(1)-C(6)-H(6A)
109.5
C(1)-C(6)-H(6B)
109.5
H(6A)-C(6)-H(6B)
109.5
C(1)-C(6)-H(6C)
109.5
H(6A)-C(6)-H(6C)
109.5
H(6B)-C(6)-H(6C)
109.5
C(2)-C(7)-H(7A)
109.5
C(2)-C(7)-H(7B)
109.5
H(7A)-C(7)-H(7B)
109.5
C(2)-C(7)-H(7C)
109.5
Calculated Geometries
1
C1 -1.5276452401 3.2504532630
-0.9672614965
N2 -0.3545756073 3.9643919482
-1.1118599572
C3 -0.1517586588 4.6164717293
-2.2899106083
C4 -1.0504047947 4.5959085194
-3.3335422658
C5 -2.2495726333 3.8681920231
-3.1935991315
C6 -2.4753119239 3.2005214630
-2.0064562358
H8 0.7814112203 5.1610051368
-2.3634527319
H9 -0.8240096777 5.1393076095
-4.2452231667
H10 -2.9783274048 3.8313607889
-3.9969272089
H11 -3.3885765928 2.6320961091
-1.8669532653
C12 -1.7096138099 1.4475675615
2.8191679405
C13 -2.8016938316 1.2351379989
1.9531354815
C14 -2.7654356666 1.8153328176
0.7012699869
C15 -1.6633484711 2.5975751426
0.3082215200
N16 -0.5961055370 2.8013909132
1.1615804168
C17 -0.6519797012 2.2195180948
2.3920165676
H18 -1.6875039078 1.0144785948
3.8140085692
H19 -3.6497542068 0.6320960030
2.2612805428
H20 -3.5898080328 1.6726316541
0.0107700244
H22 0.2028395293 2.4014525555
3.0304388701
Rh21 0.9196304928 3.9697047762
0.4707677239
C22 2.5730087370 4.0764234721
2.0241121382
C23 2.0726088230 5.4230460483
1.8654263536
C24 2.2967822608 5.8009820705
0.5091068100
C25 2.9835518668 4.7080077334
-0.1544158866
C26 3.2088789354 3.6692747555
0.7996084215
C34 2.6504321159 3.3290967760
3.3261278999
H35 2.5939229796 2.2459411862
3.1783082024
H36 3.5973086721 3.5353325749
3.8434076606
H37 1.8462049694 3.6189024704
4.0095092301
C38 1.4650618203 6.2706289958
2.9451211616
H39 0.7861663670 7.0214913065
2.5313415104
H40 0.8894507266 5.6695806339
3.6556354264
H41 2.2341736699 6.8051677358
3.5212801022
C42 1.9820754997 7.1355507776
-0.1041686855
H43 1.6799520440 7.0432092931
-1.1524686735
H44 1.1665306023 7.6363075594
0.4249559077
H45 2.8530073894 7.8052254750
-0.0792837621
C46 3.5310091705 4.7386440567
-1.5532077995
H47 3.5156332176 3.7468929404
-2.0149722241
H48 2.9630655226 5.4135515743
-2.2003716278
H49 4.5711392829 5.0920720154
-1.5644623866
C50 3.9918303280 2.4073159182
0.5826268909
H51 3.9544132433 2.0843698011
-0.4619240787
H52 5.0519950447 2.5392182084
0.8459498154
H53 3.6079191359 1.5841646333
1.1927467765
4
C1 0.1692043636 1.3213366236
0.7155259131
N2 -0.6066722083 2.4195725431
0.9118302459
C3 -1.3709526050 2.4902210235
2.0146150722
C4 -1.4039222404 1.4850324815
2.9753977370
C5 -0.6116694469 0.3558332419
2.7832208491
C6 0.1811797393 0.2750771760
1.6418433207
H8 -1.9705878799 3.3851667560
2.1185298479
H9 -2.0378890786 1.5920135066
3.8485955458
H10 -0.6089958713 -0.4517995168
3.5082233618
H11 0.8015723416 -0.5975815806
1.4789561340
C12 2.4232555605 1.4894859232
-2.8676442798
C13 2.5677213995 0.3614217116
-2.0636378369
C14 1.8384938893 0.2789612538
-0.8808067381
C15 0.9805264074 1.3223133179
-0.5226289083
N16 0.8471337397 2.4197684369
-1.3128239644
C17 1.5524482959 2.4920165428
-2.4541041485
H18 2.9699079451 1.5975474108
-3.7978745000
H19 3.2364816109 -0.4438963707
-2.3501495262
H20 1.9407568594 -0.5924300566
-0.2458749413
H22 1.4052887941 3.3861372100
-3.0458213822
Rh21 -0.5006152580 3.9056081038
-0.6064126797
C22 -0.1475302920 5.9524963964
-1.2596522553
C23 -0.9465551777 5.9579399589
-0.0288303704
C24 -2.1904540747 5.3504310863
-0.3265706822
C25 -2.3910975247 5.3074047798
-1.8382010555
C26 -0.9289504453 5.3420643235
-2.2705093753
C34 1.2167169751 6.5602862784
-1.4006448519
H35 1.7676679499 6.1300210612
-2.2403537675
H36 1.1307421945 7.6386318578
-1.5858820986
H37 1.8175251974 6.4259314190
-0.4979904778
C38 -0.5172093866 6.5726594213
1.2705024674
H39 -1.0598095154 6.1487492646
2.1188333229
H40 0.5518743180 6.4376765290
1.4511315379
H41 -0.7193985681 7.6514665800
1.2605753475
C42 -3.3477400067 5.1860876637
0.6140095263
H43 -3.8670318537 4.2368135889
0.4443548128
H44 -3.0516815227 5.2406994866
1.6648423463
H45 -4.0832956314 5.9847686851
0.4513888096
C46 -3.2403196212 6.4741196505
-2.3956305929
H47 -3.2966612511 6.4249884223
-3.4871075911
H48 -4.2633695212 6.4239576307
-2.0121311387
H49 -2.8098916199 7.4401771444
-2.1133447227
C50 -0.5437708222 5.1675148227
-3.7098726851
H51 -0.9146009948 4.2173036873
-4.1087133771
H52 -0.9893340438 5.9646471126
-4.3193670140
H53 0.5365077024 5.2169031354
-3.8693157255
H54 -2.8674262975 4.3652381487
-2.1435211128
4H
C1 -0.4752082896 1.1266614475
1.1307042442
N2 -1.1230698745 2.3078138503
0.9627991884
C3 -2.4331134849 2.3877825582
1.2522707101
C4 -3.1684362440 1.2949848994
1.6967844282
C5 -2.5182524753 0.0728198279
1.8589693257
C6 -1.1588539803 -0.0081888318
1.5783668082
H8 -2.8894729665 3.3616359802
1.1277389197
H9 -4.2247778067 1.4083229750
1.9135435729
H10 -3.0580422397 -0.8028378090
2.2044528359
H11 -0.6360610392 -0.9475140277
1.7086641579
C12 3.6580103544 1.3952718672
0.2706099412
C13 3.1625948066 0.1561912226
0.6731164340
C14 1.8071691994 0.0347535026
0.9595592731
C15 0.9692622479 1.1472063798
0.8293029801
N16 1.4618471717 2.3448930749
0.4231113172
C17 2.7744890824 2.4630714919
0.1638988534
H18 4.7089940506 1.5410364503
0.0466785403
H19 3.8210043923 -0.7010957613
0.7690014684
H20 1.4072669265 -0.9183955369
1.2831144022
H22 3.1150043847 3.4486919948
-0.1280161823
Rh21 0.0549886205 3.9192248480
0.2517308349
C22 0.9620623293 5.5733113533
-0.9292893743
C23 -0.0541855686 6.1236544106
-0.0779268117
C24 -1.3014050361 5.5284738806
-0.4654305374
C25 -1.0719416055 4.7322048173
-1.6765386448
C26 0.3045436637 4.7592189666
-1.9582653039
C34 2.3992643815 6.0051893869
-0.9640309747
H35 3.0419717231 5.2545039639
-1.4323022897
H36 2.5057298917 6.9228501862
-1.5565134508
H37 2.7858933512 6.2145603092
0.0364479005
C38 0.1379578208 7.1799972012
0.9712638246
H39 -0.5937036520 7.0896926290
1.7767366828
H40 1.1341016109 7.1344015168
1.4159808377
H41 0.0180955999 8.1738072877
0.5213672015
C42 -2.6514097486 5.9032102265
0.0728210864
H43 -3.3974464759 5.1267324773
-0.1180397990
H44 -2.6221182983 6.0971484421
1.1480177086
H45 -3.0159095482 6.8155277714
-0.4161942085
C46 -2.1514440242 4.0371635350
-2.4510642663
H47 -1.7431869534 3.3074949327
-3.1532717161
H48 -2.8495263168 3.5109703048
-1.7921177407
H49 -2.7392621515 4.7614184180
-3.0282690079
C50 1.0171171462 4.1038119557
-3.1032784854
H51 0.4005571423 3.3423493572
-3.5851423749
H52 1.2844555734 4.8462834686
-3.8652920815
H53 1.9479427910 3.6254760253
-2.7823565554
H54 0.3641529419 4.1822293275
1.7575708548
[Et
3
NH]
+
N1 -0.5831869008 0.1974570333
2.5785369573
C2 -0.6194123236 -1.2481624957
2.8053133425
C3 0.1582519783 -2.0352139245
1.7489179443
H4 -1.6687444887 -1.5625979345
2.7695587519
H5 -0.2472319078 -1.5206786515
3.8138945569
H6 0.0605696090 -3.1114353758
1.9278624681
H7 -0.2246587180 -1.8110604636
0.7486107939
H8 1.2265498285 -1.7964018587
1.7632595024
C9 0.7535483325 0.7853637162
2.7820033122
C10 1.3583892915 1.3667551129
1.5001891422
H11 1.4338701796 0.0258043240
3.1925507949
H12 0.7001570724 1.5722703769
3.5478122795
H13 2.3497169738 1.7935192130
1.6949949382
H14 1.4622817506 0.5941330071
0.7324793006
H15 0.7200502544 2.1552235711
1.0903884952
C16 -1.6435047748 0.9114315447
3.2923589673
C17 -1.8997615345 2.3116908447
2.7318599302
H18 -1.4374695610 0.9835399333
4.3797071899
H19 -2.5632636396 0.3237740577
3.1920096291
H20 -2.7336534608 2.7860619726
3.2604478869
H21 -1.0276435748 2.9640034875
2.8429656972
H22 -2.1472731468 2.2565275844
1.6673262953
Et
3
N
N1 -0.6551408176 0.2407805109
2.4348374216
C2 -0.7441816064 -1.2770365004
2.5297000734
C3 0.0518183203 -1.9903570948
1.4463539464
H4 -1.8058198792 -1.5233557259
2.4538255916
H5 -0.4040013419 -1.5385839661
3.5349642781
H6 -0.1046710805 -3.0665135852
1.5595210681
H7 -0.2901437402 -1.7152863713
0.4431701107
H8 1.1269626585 -1.8086874706
1.5172334528
C9 0.7720499021 0.7691163064
2.6460179517
C10 1.3658112915 1.3449178905
1.3676267411
H11 1.3622588139 -0.0653095282
3.0274585451
H12 0.7168408545 1.5241113586
3.4306705396
H13 2.3779996611 1.7023937630
1.5755865807
H14 1.4377861607 0.5959656886
0.5735997103
H15 0.7860959214 2.1977295153
1.0001668753
C16 -1.6705415921 0.9149031400
3.3485673908
C17 -1.8763904388 2.3850105647
3.0108129293
H18 -1.3085187827 0.7672546086
4.3691887477
H19 -2.6037092304 0.3587373940
3.2340261252
H20 -2.6383062426 2.7902038493
3.6818908116
H21 -0.9727311037 2.9852448429
3.1440703008
H22 -2.2413477346 2.5170135043
1.9866780663
H23 -0.9207671193 0.4878681543
1.4755765641
[DMF·H]
+
N1 0.0846202903 1.7759171483
-0.0552710883
C4 0.6293663337 1.0180552258
-1.2004133977
H5 -0.0936182359 0.2485963918
-1.4811389530
H6 0.8106549240 1.6846680575
-2.0401662448
H7 1.5630970190 0.5445687435
-0.8881432792
C7 -0.2128531841 1.0074920280
1.1693192774
H8 -0.9503431394 0.2372330544
0.9327586126
H9 0.7067784355 0.5359853841
1.5231029683
H10 -0.6076169916 1.6666645973
1.9431952742
C10 -0.1287328286 3.0525261924
-0.1025774963
H11 -0.5304789265 3.5553866375
0.7751172330
O12 0.1332421879 3.7322077696
-1.1878223822
H13 -0.0658941666 4.6779361431
-1.0943260793
[DMF]
N1 -0.0763718458 1.7390610119
-0.2727360878
C4 0.6021063135 1.0091243691
-1.3238119579
H5 -0.0126812406 0.1761237399
-1.6890212613
H6 0.8080973239 1.6792805299
-2.1626754872
H7 1.5560589216 0.5971783146
-0.9689825532
C7 -0.4385854345 1.0198359596
0.9364225119
H8 -1.1183261643 0.1896588919
0.7068541286
H9 0.4530668832 0.6101977453
1.4277819659
H10 -0.9336770787 1.7216304629
1.6079156254
C10 -0.3713550035 3.0679147906
-0.3913288723
H11 -0.0338874165 3.4782579542
-1.3641097731
O12 -0.9361826011 3.7473974791
0.4499081353