Tetrakis(alkoxo)diborons cross-coupled with aryl triflates at 80 ｡C in the presence of PdCl2(dppf)-dppf catalyst and KOAc in dioxane, producing arylboronates in excellent yields. The synthetic utility of the method was demonstrated by the tandem coupling between two non-identical aryl triflates to give unsymmetrical biaryls.Recent studies on the transformations of tetrakis(alkoxo)diborons1 (1) by transition-metal catalysis provide new methodology for the synthesis of organoboron compounds. The addition of 1 to alkynes,2 1,3-dienes,3 and alkenes4 is effectively catalyzed by Pt(0), Rh(I), or Au(I) complex to provide a convenient access to stereodefined bis(boryl)alkenes, bis(allyl)boronates, and bis(boryl)alkanes. The mechanism was postulated to proceed through the oxidative addition of 1 to the low-valent metal complex to form bis(boryl)metal intermediate. Alternative route from 1 to organoboron compounds is the Pd(0)-catalyzed cross-coupling with organic electrophiles, which involves the transmetalation of boryl group from 1 to R-Pd(II)-X intermediate. Haloarenes5 and allyl acetates6 smoothly coupled with 1 in the presence or absence of base to afford the corresponding aryl-and allylboronates. As a part of our program on the direct borylation of organic electrophiles using 1, we wish to report here the Pd(0)-catalyzed cross-coupling reaction of 1 with aryl triflates (2) to give arylboronates (3) (Eq. 1).

Bis(pinacolato)diboron [(Me 4 C 2 O 2 )B-B(O 2 C 2 Me 4 )] added to allenes in the presence of Pt(PPh 3 ) 4 at 80 °C or Pt(dba) 2 /(c-Hex) 3 P at 50 °C to afford 2,3-bis(boryl)-1-propenes in excellent yields. The one-pot synthesis of substituted homoallyl alcohols was also examined by the allylboration of aldehydes with diborated products followed by the coupling with organic halides.Transition-metal-catalyzed addition reaction of metal-metal reagents to allenes provides a straightforward route to 2,3-bis(metal)-1-propene and its analogs, which include synthetically useful allylmetal part and vinylmetal part in the same molecule. Although disilanes, 1 distannanes, 2 silylstannanes, 3 and germylstannanes 4 are known to add to allenes in the presence of palladium (0) catalyst, the corresponding reaction of diborons has not been reported so far presumably due to difficulties in the boron-boron bond activation by its oxidative addition to the palladium(0) complexes. 5 Recently, we have found that platinum(0) complex effectively activates the boronboron bond by the oxidative addition to give bis(boryl)platinum(II) complex. 6 This activation protocol is readily extended to the catalytic diboration of unsaturated hydrocarbons, such as alkynes, 6 alkenes, 7 and 1,3-dienes. 8 In the course of our study, we wish to disclose herein the platinum(0)-catalyzed addition of bis(pinacoalto)diboron (1) to allenes (2) to afford 2,3-bis(boryl)-1-propenes (3) (Eq. 1).(RO) 2 B B(OR) 2(RO) 2 = Me 4 C 2 O 2 + 2 1(1) Pt catalyst toluene + 1,2-Propadiene (1.5 mmol) was allowed to react with 1 (1.0 mmol) for 16 h to optimize the reaction conditions. The addition completed at 80 °C with 3 mol% of Pt(PPh 3 ) 4 in toluene, producing the corresponding 3 in 99% yield. Ligand less platinum(0) complex such as Pt(dba) 2 also gave 3 even at room temperature, but the yield of the adduct is rather low (50%) because of catalyst decomposition. The catalytic activity of platinum(0) complex is markedly influenced by the nature of ligand. Comparison of the reaction rate at room temperature with Pd(dba) 2 /PR 3 (1:1) elucidates the effectiveness of more sterically demanding ligand: e.g., (c-Hex) 3 P (85%) > (4-MeOC 6 H 4 ) 3 P

At the spinal level, the involvement of nociceptin/orphanin FQ (N/OFQ) in pain transmission is controversial. JTC-801, a selective nonpeptidergic N/OFQ antagonist, is a good tool to examine the involvement of endogenous N/OFQ in pathophysiological conditions. In the present study, we studied the effect of JTC-801 on neuropathic pain induced by L5 spinal nerve transection in mice. Thermal hyperalgesia was evident on day 3 postsurgery and maintained during the 10-day experimental period. Oral administration of JTC-801 relieved the thermal hyperalgesia in neuropathic mice in a dose-dependent manner. Following L5 nerve transection, the increase in nitric oxide synthase (NOS) activity was observed in the superficial layer of dorsal horn and around the central canal in the spinal cord by NADPH diaphorase histochemistry. Using the novel fluorescent nitric oxide (NO) detection dye diaminofluorescein-FM, we confirmed that NO production increased in the spinal slice prepared from neuropathic mice and that the increase was more prominent in the ipsilateral side to the nerve transection than in the contralateral side. These increases in NOS activity and NO production in neuropathic mice were blocked by pretreatment of oral JTC-801. Although intraperitoneal injection of the nonselective NOS inhibitor NG.-nitro-L-arginine methyl ester transiently, but significantly, attenuated neuropathic hyperalgesia, inducible NOS-deficient mice showed neuropathic pain after L5 spinal nerve transection. These results suggest that N/OFQ is involved in the maintenance of neuropathic pain and that the analgesic effect of JTC-801 on neuropathic pain is mediated by inhibition of NO production by neuronal NOS.

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Abstract. A contact hole shrink process using directed self-assembly lithography (DSAL) for sub-30 nm contact hole patterning is reported on. DSAL using graphoepitaxy and poly (styrene-block-methyl methacrylate) (PS-b-PMMA) a block copolymer (BCP) was demonstrated and characteristics of our process are spin-on-carbon prepattern and wet development. Feasibility of DSAL for semiconductor device manufacturing was investigated in terms of DSAL process window. Wet development process was optimized first; then critical dimension (CD) tolerance of prepattern was evaluated from three different aspects, which are DSA hole CD, contact edge roughness (CER), and hole open yield. Within 70 þ ∕ − 5 nm hole prepattern CD, 99.3% hole open yield was obtained and CD tolerance was 10 nm. Matching between polymer size and prepattern size is critical, because thick PS residual layer appears at the hole bottom when the prepattern holes are too small or too large and results in missing holes after pattern transfer. We verified the DSAL process on a 300-mm wafer at target prepattern CD and succeeded in patterning sub-30 nm holes on center, middle, and edge of wafer. Average prepattern CD of 72 nm could be shrunk uniformly to DSA hole pattern of 28.5 nm. By the DSAL process, CD uniformity was greatly improved from 7.6 to 1.4 nm, and CER was also improved from 3.9 to 0.73 nm. Those values represent typical DSAL rectification characteristics and are significant for semiconductor manufacturing. It is clearly demonstrated that the contact hole shrink using DSAL is a promising patterning method for next-generation lithography.