Acylphosphine Oxide Photoinitiators

Abstract

The present invention relates to a compound of formula I: [Formula 1] JPEG2025511202000030.jpg52170 is a compound of wherein R1-R3, m, and n are defined herein.The compounds of the present invention are useful as intermediates for photoinitiators that are soluble in ethylenically unsaturated organopolysiloxanes.

Description

[Technical field]

[0001] This invention relates to acylphosphine oxide photoinitiators that are useful as intermediates for organopolysiloxane-compatible photoinitiators. [Background technology]

[0002] A continuing challenge in the field of organopolysiloxane cure systems is to design photoinitiators that are compatible with organopolysiloxanes. Photoinitiators with poor compatibility are undesirable as curing agents because they separate from the silicone matrix during storage, resulting in severe haze in the cured product.

[0003] U.S. Patent No. 10,597,413(B2) (Tan) discloses -CH 2 -O-Si(OR) 3 Representative examples of acylphosphine oxides substituted with groups are given below:

[0004] [ka]

[0005] Tan discloses that these photoinitiators address the long-term solubility issue, but they also address another problem, namely the silyl ether linkage (CH 2 It is clear that the introduction of a susceptibility to acid cleavage of -OSi) would render the photoinitiator incompatible with the silicone matrix. Therefore, achieving solubility and maintaining stability would be advantageous in the art of photoinitiators in silicone systems. Summary of the Invention

[0006] The present invention addresses a need in the art in a first aspect by providing a compound of formula I:

[0007] [ka] R 1 is -phenyl-(R 3 ) m , -C(O)-phenyl-(R 2 ) m , -OC 1 -C 20 -Alkyl, or -O(CH 2 CH 2 O) x -H, Each R 2 is independently 1 -C 6 -Alkyl, C 1 -C 6 -Alkoxy, -OCH 2 -phenyl, or R 2 is adjacent to the R 2 together with a 1,3-dioxolane group or a 1,4-dioxane group, Each R 3 is independently 1 -C 6 -Alkyl or C 1 -C 6 -alkoxy, Each m is independently 0, 1, 2, or 3, n is 0, 1, or 2, and p is 0 or 1, with the proviso that when p is 0, q' is 1 to 10, and when p is 1, q' is 0 to 10 and x is 1 to 20.

[0008] In another aspect, the present invention provides a method for preparing a siloxane-functionalized photoinitiator, comprising reacting a compound of formula I in the presence of a platinum-containing catalyst under reactive conditions:

[0009] [ka] with a hydrosilane selected from the group consisting of: r is between 3 and 300.

[0010] The compounds of the present invention are useful as intermediates for organopolysiloxane-compatible photoinitiators. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] In a first aspect, the present invention is a compound represented by formula I:

[0012] [ka] R 1 is -phenyl-(R 3 ) m , -C(O)-phenyl-(R 2 ) m , -OC 1 -C 20 -Alkyl, or -O(CH 2 CH 2 O) x -H, Each R 2 is independently 1 -C 6 -Alkyl, C 1 -C 6 -Alkoxy, -OCH 2 -phenyl, or R 2 is adjacent to the R 2 together with a 1,3-dioxolane group or a 1,4-dioxane group, Each R 3 is independently 1 -C 6 -Alkyl or C 1 -C 6 -alkoxy, Each m is independently 0, 1, 2, or 3, n is 0, 1, or 2, and p is 0 or 1, with the proviso that when p is 0, q' is 1 to 10, and when p is 1, q' is 0 to 10 and x is 1 to 20.

[0013] In one embodiment, R 1 is -C(O)-phenyl-(R 2 ) m The preferred R 1Examples of groups are represented by the following structures:

[0014] [ka]

[0015] In one embodiment, when p is 0, q is 3 or 4. In another embodiment, when p is 1, q is 2 and r is from 3 or 6 or 10, up to 300 or 200 or 100 or 50.

[0016] Compounds of formula I can be prepared as described in Schemes 1-3. 1 -C(O)-phenyl-(R 2 ) m Compounds of formula I (Ia) can be prepared according to Scheme 1. The reaction conditions for each step are given in the experimental section.

[0017] Scheme 1

[0018] [ka] In the formula, when p is 0, q' is 1 to 10, and when p is 1, q' is 0 to 10.

[0019] When p is 1, the first compound in Scheme 1 can be prepared in a first step by contacting dibromobenzene, particularly p-dibromobenzene, with vinyldimethylsilyl chloride in the presence of n-butyllithium to form the following intermediate A':

[0020] [ka]

[0021] When p is 0, the first compound, particularly when q' is 2, can be prepared as described in Li, Y.-L. Song, D.-P. Pan, L. Ma, Z. Li, Y.-S. Polym. Chem. 2019, 10, 6368-6378.

[0022] Photoinitiators that are compatible with organopolysiloxane solvents can be prepared by reacting a compound of formula I with a compound of the following formula in the presence of a Pt-containing catalyst: H-Si(R 5 2 O[Si(R 5 2 )O] r -Si(R 5 2 )-H r is 3 or 6 to 300 or 200 or 100 or 50, and each R 5 is independently 1 -C 6 -alkyl or phenyl. This compatibilized photoinitiator is advantageously further reacted with a compound having the formula:

[0023] [ka] Y is Si(OMe) 3 , SiMe 3 , Si(OEt) 3 , SiMe 2 OMe, SiMe 2 OEt, Si(OSiMe 3 ) 3 , SiMe (OSiMe 3 ) 2 , or SiMe 2 (OSiMe 3 ).

[0024] Compatible photoinitiators can also be prepared by reacting a compound of formula I with either compound A or compound B in the presence of a Pt-containing catalyst.

[0025] [ka] In the formula, X is CH 2 CH 2 or CH(CH 3 ).

[0026] The reaction is typically carried out in a non-polar aprotic solvent such as hexane or xylene at elevated temperatures, generally in the range of 40°C to 90°C.

[0027] R 1 Ga-OC 1 -C 20 -Alkyl, or -O(CH 2 CH 2 O) x When it is —H, compounds of formula I (formula Ib) can be prepared according to Scheme 2.

[0028] Scheme 2

[0029] [ka] In the formula, R is HO-C 1 -C 20 -alkyl, or HO(CH 2 CH 2 O) x -H.

[0030] R 1 -phenyl-(R 3 ) n When it is, compounds of formula I(Ic) can be prepared according to Scheme 3.

[0031] Scheme 3

[0032] [ka]

[0033] The organopolysiloxane compatible photoinitiators prepared from the compounds of formula I can be vigorously mixed with ethylenically unsaturated organopolysiloxanes to form homogeneous, non-cloudy compositions. Suitable ethylenically unsaturated polyorganosiloxanes include diethylenically unsaturated compounds having the formula:

[0034] [ka] In the formula, y is 10 to 10,000, and R 5 is as defined above. Commercially available polyorganosiloxanes include XIAMETER™ RBL-9119 organopolysiloxane and XIAMETER™ RBL-9128 organopolysiloxane (XIAMETER is a trademark of The Dow Chemical Company or its affiliates). The concentration of the photoinitiator core ranges from 0.1% or 0.2% to 4% or 2% by weight based on the weight of the composition. As used herein, "photoinitiator core" refers to the following fragment:

[0035] [ka] EXAMPLES

[0036] Intermediate Example 1 Preparation of (4-(but-3-en-1-yl)phenyl)dichlorophosphane In a glove box, a 500 mL round-bottom flask was charged with 1-bromo-4-(but-3-en-1-yl)benzene (17.1 g), dry THF (118 mL), and dry diethyl ether (37 mL). The flask was sealed and transferred to a fume hood. The mixture was then purified by N 2The mixture was stirred under reduced pressure and cooled to -78 °C, then n-butyllithium (n-BuLi (2.5 M in hexanes, 34.0 mL) was added dropwise to the mixture. The mixture was stirred for 30 min, followed by chlorobis(diethylamino)phosphine (17.9 mL, 85.1 mmol). The mixture was stirred for 20 min and allowed to warm to ambient temperature. The solution was poured into a separatory funnel containing diethyl ether and water. The phases were separated and the aqueous phase was extracted several times with diethyl ether. The combined organic fractions were washed with brine and MgSO 4 and concentrated in vacuo.

[0037] The crude oil was transferred to a 1000 mL round bottom flask which was placed in a glove box. The oil was dissolved in dry diethyl ether (100 mL). The mixture was stirred and treated dropwise with HCl (2.0 M in diethyl ether, 162 mL, 324 mmol, 4.00 equiv), precipitating a white solid. After 2 h, the slurry was filtered and the filtrate was concentrated. A colorless oil was isolated (15.9 g, 84%) which was used in the next step without further purification.

[0038] 1 H NMR (500MHz, C 6 D 6 )δ7.63-7.40(m,2H),6.86-6.76(m,2H),5.62(ddt,J=18.1,9.5,6.6Hz,1H),5. 00-4.83(m,2H),2.35(dd,J=8.8,6.7Hz,2H),2.06(tdt,J=7.8,6.5,1.5Hz,2H).

[0039] 13 C NMR (126MHz, C 6 D 6 )δ146.99,137.73(d,J=51.8Hz),137.14,130.12(d,J=32.1Hz),128.85(d,J=8.3Hz),115.16,35.02,34.73.

[0040] 31 P NMR (202 MHz, C 6 D 6 )δ161.94.

[0041] Intermediate Example Preparation of 2-(4-(but-3-en-1-yl)phenyl)phosphane In a glove box, add diethyl ether (100 mL) and LiAlH 4 (2.0M in THF, 19.8 mL, 39.6 mmol, 0.60 equiv). The solution was stirred vigorously and Intermediate Example 1 (15.4 g, 66.1 mmol, 1.00 equiv) in diethyl ether (65 mL) was added dropwise to the solution over 10 min. The mixture was stirred for 30 min, then solid Glauber's salt (25.5 g, 79.3 mmol, 1.20 equiv) was carefully added. The mixture was stirred for 60 min, the liquid was decanted, filtered through a 0.45 μm syringe filter, and concentrated to give a colorless oil (9.73 g, 90%) which was used in the next step without further purification.

[0042] 1 H NMR (500MHz, C 6 D 6 )δ7.33-7.22(m,2H),6.88-6.79(m,2H),5.70(ddt,J=16.9,10.2,6.6Hz,1H),5.02-4.89(m, 2H), 3.87(d,J=198.5Hz,2H),2.44(dd,J=8.8,6.7Hz,2H),2.16(tdt,J=7.9,6.6,1.5Hz,2H).

[0043] 13 C NMR (126MHz, C 6 D 6 )δ141.77,137.65,134.92(d,J=15.7Hz),134.19(dt,J=26.8,9.8Hz),128.56(d,J=6.2Hz),114.84,35.26,34.96.

[0044] 31 P NMR (202MHz, C 6 D 6 )δ-125.28(tt,J=197.6,7.3Hz).

[0045] Example 1 Preparation of ((4-(but-3-en-1-yl)phenyl)phosphoryl)bis(mesitylmethanone) In a glove box, a solution of Intermediate Example 2 (9.73 g, 59.3 mmol, 1.00 equiv) in dry THF (300 mL) was treated with sodium tert-butoxide (Nat-OBu, 11.4 g, 118 mmol, 2.00 equiv) and then 2,4,6-trimethylbenzoyl chloride (19.8 mL, 118 mmol, 2.00 equiv) was added dropwise to the mixture. The mixture was stirred overnight. Crude 31 P NMR spectroscopic analysis showed that the phosphine was partially consumed. Additional amounts of Nat-OBu (3.99 g) and benzoyl chloride (6.9 mL) were added to the reaction mixture. After 5 h, the mixture was filtered to remove sodium chloride, and the filtrate was removed from the glove box and concentrated in vacuo. The crude residue was dissolved in dichloromethane (200 mL) and the solution was treated with hydrogen peroxide (6.0 mL, 30 wt%). The mixture was stirred overnight at ambient temperature, then treated with aqueous sodium bisulfite (100 mL) and stirred until the organic phase was negative to a peroxide strip test. The phases were separated and concentrated over Celite for chromatography on silica gel (0-50% EtOAc in hexanes). A yellow oil (13 g) containing the product and some other impurities was isolated. A second column purification was performed, after which Intermediate Example 3 (11.3 g) was isolated as a yellow oil.

[0046] 1 H NMR (500 MHz, CDCl 3 )δ7.78(dd,J=10.1,8.1Hz,2H),7.23(dd,J=8.3,3.0Hz,2H),6.78(s,4H),5.77(ddt,J=16.0,10.7, 6.6Hz, 1H), 5.20-4.61 (m, 2H), 2.74 (t, J=7.6Hz, 2H), 2.39-2.32 (m, 2H), 2.25 (s, 6H), 2.14 (s, 12H).

[0047] 13 C NMR (126 MHz, CDCl 3)δ216.37(d,J=59.9Hz),147.41(d,J=2.9Hz),140.92,137.12,135.73(d,J=41.8Hz),135.47,132.19( d,J=8.3Hz),128.93,128.77(d,J=11.6Hz),122.82(d,J=78.0Hz),115.50,35.32,34.93,21.18,19.60.

[0048] Intermediate Example Preparation of 3-(4-bromophenyl)dimethyl(vinyl)silane Add N to a 1000 mL, 3-neck round-bottom flask equipped with an addition funnel. 2 Dry THF (425 mL) and 1,4-dibromobenzene (20.0 g, 84.8 mmol, 1.00 equiv) were charged under a blanket of water. The mixture was stirred and cooled to -78°C. n-BuLi solution (2.5 M in hexanes, 35.6 mL, 89.0 mmol, 1.05 equiv) was added dropwise to the dibromobenzene solution over 25 min. Stirring was continued for an additional 50 min after addition of the n-BuLi solution was complete.

[0049] Chlorodimethylvinylsilane (12.9 mL, 93.3 mmol, 1.10 equiv) was added dropwise to the reaction mixture with stirring. The mixture was allowed to warm gradually to room temperature over 1 h, after which the mixture was quenched with aqueous ammonium chloride. The product was extracted several times with ethyl acetate. The combined organic fractions were dried over sodium sulfate and concentrated. The crude oil was purified under vacuum (450 mTorr, 52-60° C.) to give Intermediate Example 4 (18.75 g) as a colorless oil.

[0050] 1 H NMR (400 MHz, CDCl 3 )δ7.53-7.44(m,2H),7.40-7.33(m,2H),6.25(dd,J=20.2,14.6Hz,1H),6.06(dd,J=14.6,3.8Hz,1H),5.74(dd,J=20.2,3.8Hz,1H),0.33(s,6H).

[0051] 13 C NMR (101 MHz, CDCl3 )δ137.33,137.22,135.42,133.26,130.90,123.83,-3.03.

[0052] Example 2 - Preparation of ((4-(dimethyl(vinyl)silyl)phenyl)phosphoryl)bis(mesitylmethanone) In a glove box, a 250 mL round bottom flask was charged with Intermediate Example 3 (4.31 g, 17.9 mmol, 1.00 equiv), dry THF (26 mL), and dry diethyl ether (8 mL). The flask was sealed and transferred to a fume hood. The mixture was stirred under nitrogen and cooled to -78 °C. n-BuLi (2.5 M in hexanes, 7.51 mL, 18.8 mmol, 1.05 equiv) was added dropwise. The mixture was stirred for 30 min, after which chlorobis(diisopropylamino)phosphine (5.01 g, 18.8 mmol, 1.05 equiv) was added as a solid. The mixture was stirred and allowed to warm to ambient temperature over 2 h. The solution was poured into a separatory funnel containing diethyl ether and water. The phases were separated and the aqueous phase was extracted several times with diethyl ether. The combined organic fractions were washed with brine and MgSO 4 It was dried at 40° C. and concentrated on a rotary evaporator.

[0053] The crude oil was transferred to a 250 mL round bottom flask, which was placed in the glove box. The oil was dissolved in dry diethyl ether (20 mL). The flask was sealed and transferred to a fume hood. The mixture was stirred and N 2 The mixture was cooled to 0° C. under 100° C. Then, HCl (2.0 M in diethyl ether, 35.7 mL, 71.5 mmol, 4.00 equiv.) was added dropwise, causing a white solid to precipitate. Stirring was continued for 2 h, after which the slurry was filtered and the filtrate was concentrated. The crude residue was mixed with diethyl ether and hexanes and filtered again. The filtrate was concentrated to give a colorless oil (4.59 g). The crude material was used in the next step without further purification.

[0054] In a glove box, add diethyl ether (44 mL) and LiAlH to a 150 mL jar with vigorous stirring. 4(2.0 M in THF, 5.23 mL, 10.5 mmol, 0.60 equiv.). The crude material from the previous step (4.59 g, 17.4 mmol, 1.00 equiv.) was added to LiAlH 4 The solution was added dropwise over 5 min. The mixture was stirred for 30 min, after which solid Glauber's salt (6.74 g, 20.9 mmol, 1.20 equiv) was carefully added. Stirring was continued for 14 h, after which the solution was filtered and the filtrate was concentrated to give 2.71 g of crude product as a colorless oil. The crude material was used in the next step without further purification.

[0055] A solution of the crude material from the previous step (2.71 g) in dry THF (70 mL) was treated with dry Nat-OBu (2.68 g, 27.9 mmol, 2.00 equiv.), followed by the dropwise addition of 2,4,6-trimethylbenzoyl chloride (4.65 mL, 27.9 mmol, 2.00 equiv.). The mixture was stirred for 3 h, and then the mixture was filtered to remove sodium chloride.

[0056] The filtrate was removed from the glove box and concentrated in vacuo. The crude residue was dissolved in dichloromethane (50 mL) and the solution was treated with hydrogen peroxide (1.4 mL, 30 wt%). The mixture was stirred at ambient temperature overnight and then treated with aqueous sodium bisulfite (30 mL). The phases were separated and the organic phase was concentrated in the presence of silica gel to facilitate liquid chromatography on silica gel (0-50% EtOAc in hexanes). Intermediate Example 5 (1.98 g) was isolated as a yellow oil that solidified on standing.

[0057] 1 H NMR (500 MHz, CDCl 3 )δ7.90-7.79(m,2H),7.56(dd,J=8.0,3.3Hz,2H),6.78(s,4H),6.24(dd,J=20.2,14.7Hz,1H),6. 07(dd,J=14.6,3.6Hz,1H),5.71(dd,J=20.3,3.7Hz,1H),2.25(s,6H),2.14(s,12H),0.35(s,6H).

[0058] 13C NMR (126 MHz, CDCl 3 )δ215.87(d,J=58.9Hz),144.76(d,J=2.5Hz),140.99,136.91,135.84,135.52,133.67(d,J =10.8Hz),133.55,131.01(d,J=7.6Hz),128.95,126.27(d,J=75.6Hz),21.18,19.64,-3.17.

[0059] 31 P NMR (202MHz, CDCl 3 ) δ7.19(t,J=10.6Hz).

[0060] In the following examples, M'D r M' polysiloxane is H-Si(Me 2 )O[Si(Me 2 )O] r -Si(Me 2 )-H.

[0061] Example 3 -M'D 38 Preparation of M' polysiloxane substituted photoinitiators The compound of Example 1 (0.07 g) was dissolved in dry hexane (3.0 mL) and M'D 38 M' polysiloxane (1.72 g) was mixed in a glove box. The mixture was stirred at 50° C. until the solids were dissolved. Karstedt's catalyst (2 wt % Pt in xylene, 0.03 mL) was added and the mixture was stirred overnight. The consumption of the compound of Example 1 was 1 Monitored by H NMR spectroscopy, additional Karstedt's catalyst was added until <5% of the alkene remained. Vinyltrimethoxysilane was added to react with the remaining Si-H groups.

[0062] The volatiles were removed by vacuum pump leaving a yellow oil. The product mixture was calculated to contain 4.0 wt% photoinitiator.

[0063] Example 4 -M'D 7 Preparation of M' polysiloxane substituted photoinitiators M'D 7The procedure described in Example 3 was followed except that M' polysiloxane (0.55 g) was used. The product mixture was calculated to contain 15.3 wt% photoinitiator.

[0064] Example 5 -M'D 14 Preparation of M' polysiloxane substituted photoinitiators M'D 14 The procedure described in Example 3 was followed except that M' polysiloxane (0.99 g) was used. The product mixture was calculated to contain 9.1 wt% photoinitiator.

[0065] In Examples 1 to 3, the following products and by-products were identified.

[0066] [ka]

[0067] Example 6 -M'D 38 Preparation of M' polysiloxane substituted photoinitiators The compound of Example 2 (0.10 g) was dissolved in dry toluene (1.5 mL) and M'D 38 M' polysiloxane (0.60 g) was mixed in a glove box. The mixture was stirred at 80° C. until the solids were dissolved. Karstedt's catalyst (2 wt % Pt in xylene, 0.012 mL) was added to the mixture and stirring was continued for 1 hour. The consumption of the compound of Example 2 was 1 The reaction was monitored by H NMR spectroscopy and additional Karstedt's catalyst was added until <5% of the alkene remained. Vinyltrimethoxysilane was added to react with the remaining Si-H groups. Volatiles were removed in vacuo leaving a yellow oil. The product mixture was calculated to contain 14.5 wt% photoinitiator.

[0068] Example 7 -M'D 7 Preparation of M' polysiloxane substituted photoinitiators M'D 7 The procedure described in Example 6 was followed except that M' polysiloxane (0.14 g) was used. The product mixture was calculated to contain 43.5 wt% photoinitiator.

[0069] Example 8 -M'D 14 Preparation of M' polysiloxane substituted photoinitiators M'D 14 The procedure described in Example 6 was followed except that M' polysiloxane (0.24 g) was used. The product mixture was calculated to contain 30.0 wt.% photoinitiator. The following products and by-products were identified for Examples 4-6:

[0070] [ka]

[0071] Example 9 - Preparation of Compound A-Substituted Photoinitiators The compound of Example 2 (0.11 g) was mixed with dry toluene (1.5 mL) under stirring in a glove box at 80° C. until the solid dissolved. Compound A (0.19 mL) was added to the mixture along with Karstedt's catalyst (2 wt % Pt in xylene, 0.06 mL) and the mixture was stirred for 1 hour. The consumption of the compound of Example 2 was 1 The reaction was monitored by H NMR spectroscopy. Additional catalyst was added until <5 wt% starting material remained. Excess vinyltrimethoxysilane was then added and stirring was continued until the Si-H functionality was completely consumed. The volatiles were removed in vacuo leaving a yellow oil. The product was calculated to contain 18 wt% photoinitiator. The following products were identified:

[0072] [ka]

[0073] Example 10 - Preparation of Compound B-Substituted Photoinitiators The procedure described in Example 9 was followed except that Compound B (0.10 mL) was used. The product was calculated to contain 20% by weight of photoinitiator. The following products were identified:

[0074] [ka]

[0075] Example 11 - Preparation of Compound A-Substituted Photoinitiators The compound of Example 1 (0.14 g) was mixed with dry hexane (3.0 mL) and dry toluene (1.5 mL) in a glove box with stirring at 50° C. until the solids dissolved. Compound A (1.03 mL) was added to the mixture along with Karstedt's catalyst (2 wt % Pt in xylene, 0.06 mL) and the mixture was stirred for 1 hour. The consumption of the compound of Example 1 was 1 The reaction was monitored by H NMR spectroscopy. Additional catalyst was added until <5 wt% starting material remained. Excess vinyltrimethoxysilane was then added and stirring was continued until the Si-H functionality was completely consumed. The volatiles were removed in vacuo leaving a yellow oil. The product was calculated to contain 18 wt% photoinitiator. The following products were identified:

[0076] [ka]

[0077] Photoinitiator composition preparation Each of the compounds prepared in Examples 3-11 was mixed with enough XIAMETER® RBL-9119 organopolysiloxane to form a 0.5% by weight mixture relative to the photoinitiator core. The compositions were visually inspected for homogeneity. No samples were observed containing solid particles or phase-separated oil droplets. Thus, all were found to be homogeneous.

[0078] After visual inspection for uniformity, each vial was placed in a robotic imaging station. Photographs were taken at ambient temperature to measure phase clarity. Phase clarity was determined by subtracting the image background, cropping the image, thresholding pixel intensities using an Otsu threshold, and calculating the average intensity over the remaining pixels. Pixel intensity (phase clarity) was reported as a value between 0 (transparent) and 255 (opaque). A pixel intensity of <120 was considered passing clarity.

[0079] [Table 1]

[0080] Compositions prepared from the photoinitiator compounds of the present invention have been found to meet the criteria of homogeneity, transparency, and stability against degradation.

Claims

1. A compound of formula I, 【Chemistry 1】 R １ is -phenyl-(R ３ ) ｍ , —C(O)-phenyl-(R ２ ) ｍ , -O-C １ -C ２０ -alkyl, or -O(CH ２ CH ２ O) ｘ -H, Each R ２ is independently １ -C ６ -Alkyl, C １ -C ６ -Alkoxy, -OCH ２ -phenyl, or R ２ is adjacent to R on the phenyl ring ２ together with a 1,3-dioxolane group or a 1,4-dioxane group, Each R ３ is independently １ -C ６ -Alkyl or C １ -C ６ -alkoxy, Compounds wherein each m is independently 0, 1, 2, or 3; n is 0, 1, or 2; and p is 0 or 1, with the proviso that when p is 0, q' is 1-10, and when p is 1, q' is 0-10 and x is 1-20.

2. R １ is -C(O)-phenyl-(R ２ ) ｍ wherein n is 0, p is 1 and q′ is 2.

3. m is 3, and each R ２ is methyl, R １ is represented by the following fragment: 【Chemistry 2】 The compound according to claim 2.

4. R １ But -O-C １ -C ２０ -alkyl, or -O(CH ２ CH ２ O) ｘ -H, n is 0, p is 1, q' is 2, and each R ２ is methyl, R １ is represented by the following fragment: 【Chemistry 3】 The compound of claim 1.

5. R １ -phenyl-(R ３ ) ｍ where n is 0, p is 1, q′ is 2, and each R ２ is methyl, R １ is represented by the following fragment: 【Chemistry 4】 The compound of claim 1.

6. 1. A process for preparing a siloxane-functionalized photoinitiator, comprising reacting a compound of formula I of claim 1 with a platinum-containing catalyst under reactive conditions, 【Chemistry 5】 with a hydrosilane selected from the group consisting of r is 3 to 300, and each R ５ is independently C1-C6-alkyl or phenyl.

7. The hydrosilane has the formula: 【Chemistry 6】 The process further comprises the step of contacting the reaction product of the compound of formula I and the hydrosilane in the presence of a platinum-containing catalyst with a compound of the formula: 【Chemistry 7】 forming a compound having the formula 【Chemistry 8】 Y is Si(OMe) ３ , SiMe ３ , Si(OEt) ３ , SiMe ２ OMe, SiMe ２ OEt, Si(OSiMe ３ ) ３ , SiMe (OSiMe ３ ) ２ , or SiMe ２ (OSiMe ３ 7. The process of claim 6, wherein

8. r is 6 to 50 and Y is Si(OMe) ３ 8. The process of claim 7, wherein

9. The hydrosilane is 【Chemistry 9】 The process according to claim 6, wherein

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